JP5707237B2 - Pneumatic tire - Google Patents

Description

  The present invention relates to a pneumatic tire, and more particularly, to a pneumatic tire having high adhesion durability between a cord and a coating rubber in a belt layer and low rolling resistance.

  Recently, steel cord reinforced pneumatic tires using steel cords as a reinforcing material for belts are gaining market share. In such a steel cord reinforced pneumatic tire, in order to improve the durability of the belt, it is effective to improve the adhesion between the rubber and the steel cord. In general, the steel cord is plated with zinc, brass or the like in order to improve the adhesion between the rubber and the steel cord.

  On the other hand, a rubber composition containing resorcin, resorcin-formaldehyde resin (RF resin), or the like is used for the steel cord coating rubber, but in the rubber composition, bloom of resorcin or RF resin occurs. When the rubber composition is compounded due to the generation of the bloom and then stored for a long time from the vulcanization adhesion, there is a problem that the adhesiveness is lowered.

  In contrast, JP-A-2005-290373 (the following Patent Document 1) discloses that a rubber composition containing a compound having a specific structure or a composition containing the compound as a main component is used as a steel cord coating rubber. By applying, it is disclosed that the adhesion between the rubber and the steel cord can be improved while suppressing the occurrence of bloom.

JP 2005-290373 A

  On the other hand, in consideration of the environment, in order to improve the fuel efficiency of the tire, it is required to reduce the rolling resistance of the tire. However, with the conventional method, it has been difficult to reduce the rolling resistance of the tire while improving the durability of the belt.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a pneumatic tire having high durability for bonding between a cord and a coating rubber in a belt layer and having low rolling resistance.

  As a result of intensive studies to achieve the above object, the present inventors have applied a specific laminate to the inner liner of a tire, while having a compound having a specific structure or a compound as a main component in the coating rubber of the belt layer. It was found that by applying a rubber composition containing the composition to be applied, the rolling resistance of the tire can be reduced while improving the adhesion durability between the cord and the coating rubber in the belt layer, and the present invention has been completed. .

（式中、Ｒは炭素数１〜１６の２価の脂肪族基、又は２価の芳香族基を表す）で表される化合物を０．１〜１０質量部配合してなるゴム組成物を適用した
ことを特徴とする。 That is, the pneumatic tire of the present invention comprises a carcass, a belt composed of one or more belt layers disposed on the outer side in the tire radial direction of the carcass, and an inner liner disposed on the tire inner surface side of the carcass,
A laminate comprising a total of 7 or more layers of a barrier layer made of a resin composition having a thickness of 0.001 to 10 μm and an elastomer layer having a thickness of 0.001 to 40 μm made of an elastomer composition, Apply,
The belt layer is formed by coating a cord with a coating rubber, and at least one coating rubber of the belt layer has the following general formula (1) with respect to 100 parts by mass of a rubber component:

(Wherein R represents a divalent aliphatic group having 1 to 16 carbon atoms, or a divalent aromatic group) It is characterized by being applied.

（式中、Ｒは炭素数１〜１６の２価の脂肪族基、又は２価の芳香族基を表す）で表される化合物が６０〜１００重量％、下記一般式（３）：

（式中、Ｒは炭素数１〜１６の２価の脂肪族基、又は２価の芳香族基を表し、ｎは２〜６の整数を示す）で表され且つｎ＝２の化合物が０〜２０重量％、上記一般式（３）で表され且つｎ＝３の化合物が０〜１０重量％及び上記一般式（３）で表され且つｎ＝４〜６の化合物が合計で０〜１０重量％からなる組成物を０．１〜１０質量部配合してなるゴム組成物を適用した
ことを特徴とする。 Further, another pneumatic tire of the present invention includes a carcass, a belt composed of one or more belt layers disposed on the outer side in the tire radial direction of the carcass, and an inner liner disposed on the tire inner surface side of the carcass. Prepared,
A laminate comprising a total of 7 or more layers of a barrier layer made of a resin composition having a thickness of 0.001 to 10 μm and an elastomer layer having a thickness of 0.001 to 40 μm made of an elastomer composition, Apply,
The belt layer is formed by covering a cord with a coating rubber, and at least one coating rubber of the belt layer is represented by the following general formula (2) with respect to 100 parts by mass of a rubber component:

(Wherein R represents a divalent aliphatic group having 1 to 16 carbon atoms or a divalent aromatic group), 60 to 100% by weight of a compound represented by the following general formula (3):

(Wherein R represents a divalent aliphatic group having 1 to 16 carbon atoms or a divalent aromatic group, and n represents an integer of 2 to 6) and n = 2 is a compound represented by 0 0 to 10% by weight, 0 to 10% by weight of the compound represented by the above general formula (3) and n = 3 and 0 to 10% by weight of the compound represented by the above general formula (3) and n = 4 to 6 A rubber composition obtained by blending 0.1 to 10 parts by mass of a composition consisting of% by weight is applied.

  In a preferred example of the pneumatic tire of the present invention, the elastomer composition constituting the elastomer layer is obtained by dispersing a soft material having a Young's modulus at 23 ° C. lower than that of the elastomer in the elastomer. Here, the soft material preferably has a molecular weight of 10,000 or less, and more preferably 1,000 or less.

  In another preferable example of the pneumatic tire of the present invention, the elastomer composition constituting the elastomer layer includes a polyurethane-based thermoplastic elastomer.

  In another preferable example of the pneumatic tire of the present invention, the resin composition constituting the barrier layer is obtained by dispersing a soft material having a Young's modulus at 23 ° C. lower than that of the resin in the resin. Here, the soft material preferably has a functional group capable of reacting with a hydroxyl group. Further, the soft material preferably has a molecular weight of 10,000 or less, and more preferably 1,000 or less.

  In the pneumatic tire of the present invention, the resin composition constituting the barrier layer includes an ethylene-vinyl alcohol copolymer, a modified ethylene-vinyl alcohol copolymer, a polyamide resin, a polyvinylidene chloride resin, a polyethylene terephthalate, and a polyacrylonitrile. It is preferable to contain at least one selected from the group consisting of: ethylene-vinyl alcohol copolymer and / or modified ethylene-vinyl alcohol copolymer.

  In another preferred embodiment of the pneumatic tire of the present invention, the barrier layer and / or the elastomer layer are crosslinked by irradiation with active energy rays.

  In another preferred embodiment of the pneumatic tire of the present invention, the rubber component of the rubber composition applied to the coating rubber contains natural rubber.

  In another preferred embodiment of the pneumatic tire of the present invention, the rubber composition applied to the coating rubber further contains 2 to 9 parts by mass of sulfur with respect to 100 parts by mass of the rubber component.

  According to the present invention, it is possible to provide a pneumatic tire that has high adhesion durability between the cord and the coating rubber in the belt layer and has low rolling resistance.

It is a fragmentary sectional view of an example of the pneumatic tire of the present invention.

<Pneumatic tire>
Hereinafter, the pneumatic tire of the present invention will be described in detail with reference to the drawings. FIG. 1 is a partial cross-sectional view of an example of the pneumatic tire of the present invention. The tire shown in FIG. 1 has a pair of bead portions 1, a pair of sidewall portions 2, and a tread portion 3 connected to both sidewall portions 2, and extends in a toroid shape between the pair of bead portions 1. A carcass 4 that reinforces each of these parts 1, 2, and 3, and a belt 5 comprising two belt layers disposed on the outer side of the crown portion of the carcass 4 in the tire radial direction. An inner liner 6 is disposed on the inner surface of the tire.

  In the illustrated example of the tire, the carcass 4 has a main body portion extending in a toroidal shape between a pair of bead cores 7 embedded in the bead portion 1, and around each bead core 7 from the inner side to the outer side in the tire width direction. In the tire of the present invention, the number of plies and the structure of the carcass 4 are not limited to this.

  In the illustrated tire, the belt 5 includes two belt layers. However, in the tire of the present invention, the number of belt layers constituting the belt 5 is not limited thereto. Here, in the pneumatic tire of the present invention, the belt layer is formed by covering a cord, preferably a steel cord, with a coating rubber, and is usually arranged so that the cord extends while being inclined with respect to the tire equatorial plane. The belt layers are laminated so that the cords constituting the belt layers intersect with each other across the equator plane. In the pneumatic tire of the present invention, an inner liner is applied while applying a rubber composition in which a compound having a specific structure described later or a composition containing the compound as a main component is added to at least one coating rubber of the belt layer. 6 is applied to a laminate including a barrier layer and an elastomer layer described later.

  In addition, the material, shape, and arrangement used for those portions of a normal tire can be appropriately employed for the tread surface portion, sidewall portion, bead portion, and the like of the pneumatic tire of the present invention. Moreover, as gas with which this tire is filled, inert gas, such as nitrogen, argon, helium other than normal or the air which adjusted oxygen partial pressure, can be used.

  In the pneumatic tire of the present invention, since the air permeability of a laminate including a barrier layer and an elastomer layer, which will be described later, is very low, it is possible to reduce the weight of the tire by making the inner liner 6 thin. Moreover, rolling resistance of the tire can be reduced by reducing the weight of the tire. Moreover, the adhesiveness between the cord and the rubber can be improved by applying a rubber composition in which a compound having a specific structure to be described later or a composition containing the compound as a main component is applied to the coating rubber of the belt layer.

  Surprisingly, in the pneumatic tire of the present invention, since the air permeability of the laminate including the barrier layer and the elastomer layer, which will be described later, is very low, the permeation of oxygen to the belt 5 is suppressed, and the belt As a result, it is possible to greatly improve the durability of bonding between the cord and the rubber in the belt 5.

<Inner liner>
In the pneumatic tire of the present invention, an inner liner 6 is disposed on the tire inner surface side of the carcass 4, a barrier layer made of a resin composition having a thickness of 0.001 to 10 μm, and an elastomer composition A laminate including a total of 7 or more elastomer layers having a thickness of 0.001 to 40 μm is applied.

  The laminate used for the inner liner of the pneumatic tire of the present invention includes a barrier layer and an elastomer layer, and the total number of the barrier layer and the elastomer layer is 7 or more. With such a laminated body, it is possible to prevent defects such as pinholes and cracks generated in a certain layer from progressing to adjacent layers, so that cracks and fractures throughout the laminated body can be prevented, and high gas barrier properties In addition, durability such as crack resistance can be maintained. Moreover, in order to further demonstrate the effect exhibited by the above-described laminate, it is preferable that the barrier layer and the elastomer layer are alternately laminated, and the barrier layer is more likely to crack than the elastomer layer. Therefore, it is preferable that the surface of the laminate is formed of an elastomer layer. Accordingly, the number of barrier layers is preferably 3 or more, and the number of elastomer layers is preferably 4 or more. In addition, from the viewpoint of sufficiently maintaining the gas barrier properties and crack resistance of the laminate, the total number of barrier layers and elastomer layers needs to be 7 or more, preferably 11 or more, More preferably, it is 15 layers or more. In addition, the upper limit of the total number of layers of a barrier layer and an elastomer layer is not specifically limited.

  In the above laminate, the barrier layer has a thickness of 0.001 to 10 μm, and the elastomer layer has a thickness of 0.001 to 40 μm. By setting the thicknesses of the barrier layer and the elastomer layer in the above range, the number of layers constituting the laminate can be increased, and the total thickness is the same, but the laminate is less than the laminate having a small number of layers. The gas barrier property and crack resistance of the body can be improved.

  For example, polystyrene is mentioned as an example of a material used for the barrier layer. Polystyrene is known as a brittle material, and a layer made of polystyrene may break due to elongation of about 1.5% at room temperature. is there. However, in “Polymer, 1993, vol. 34 (10), 2148-2154”, a layer made of a ductile material and a layer made of polystyrene are laminated, and the thickness of the layer made of polystyrene is made 1 μm or less. Thus, it has been reported that a layer made of polystyrene is modified from brittle to ductile. That is, it is considered that even a layer made of a brittle material such as polystyrene can be modified to toughness by making the layer very thin. The present inventors paid attention to such a concept and found a laminate capable of achieving both excellent gas barrier properties and crack resistance.

  The barrier layer requires that the lower limit of the thickness is 0.001 μm, preferably 0.005 μm, and more preferably 0.01 μm. Further, the upper limit of the thickness of the barrier layer is required to be 10 μm, preferably 7 μm, more preferably 5 μm, further preferably 3 μm, further preferably 1 μm, still more preferably 0.5 μm, and further 0.2 μm. More preferably, 0.1 μm is particularly preferable, and 0.05 μm is most preferable. When the thickness of the barrier layer is less than 0.001 μm, it becomes difficult to form the film with a uniform thickness, and the gas barrier property and crack property of the laminate may be deteriorated. On the other hand, if the thickness of the barrier layer exceeds 10 μm, depending on the thickness of the laminate, the number of barrier layers constituting the laminate cannot be sufficiently secured, and the gas barrier property and crack resistance may be lowered. The toughness may not be imparted to the barrier layer.

  For the same reason, the above-mentioned elastomer layer requires that the lower limit of the thickness is 0.001 μm, preferably 0.005 μm, and more preferably 0.01 μm. For the same reason, the upper limit of the thickness of the elastomer layer needs to be 40 μm, preferably 30 μm, and more preferably 20 μm. The total thickness of the elastomer layer is equal to or greater than the total thickness of the barrier layer, that is, the ratio of the total thickness of the elastomer layer to the total thickness of the barrier layer (elastomer layer / barrier layer). It is preferable that the thickness is 1 or more. Thereby, the bending fatigue characteristic until the laminated body reaches the whole layer breakage is improved.

  The thickness of the laminate is preferably in the range of 0.1 to 1000 μm, more preferably in the range of 0.5 to 750 μm, and still more preferably in the range of 1 to 500 μm. If the thickness of the laminate is within the above range, it is suitable as an inner liner, and in combination with limiting the thickness of the barrier layer and the elastomer layer, the gas barrier property, crack resistance, etc. can be further improved. it can.

  In the laminate, the barrier layer and / or the elastomer layer are preferably cross-linked by irradiation with active energy rays. By cross-linking the barrier layer and / or the elastomer layer, preferably both the barrier layer and the elastomer layer, by irradiation with active energy rays, the affinity between the laminated layers can be improved and high adhesiveness can be expressed. As a result, the interlayer adhesion of the laminate, and thus the gas barrier properties and crack resistance, can be significantly improved. The active energy rays mean those having energy quanta among electromagnetic waves or charged particle rays, and specific examples include ultraviolet rays, γ rays, electron beams, etc. Among them, improvement of interlayer adhesion From the viewpoint of the effect, an electron beam is preferable. When irradiating an electron beam as an active energy ray, the electron beam source is, for example, a Cockroft Walton type, a bandegraft type, a resonant transformer type, an insulated core transformer type, or a linear type, a dynamitron type, a high frequency type, etc. Various electron beam accelerators can be used, the acceleration voltage is usually 100 to 500 kV, and the irradiation dose is usually in the range of 5 to 600 kGy. Moreover, when using an ultraviolet-ray as an active energy ray, it is good to irradiate what contains the ultraviolet-ray with a wavelength of 190-380 nm. There is no restriction | limiting in particular as an ultraviolet-ray source, For example, a high pressure mercury lamp, a low pressure mercury lamp, a metal halide lamp, a carbon arc lamp etc. are used.

  The elastomer layer constituting the laminate is a layer made of an elastomer composition in which an elastomer exists as a matrix, and the elastomer layer is an elastomer in which a soft material having a Young's modulus at 23 ° C. lower than that of the elastomer is dispersed in the elastomer. It preferably consists of a composition. The matrix means a continuous phase. Moreover, the elastomer composition may be comprised only from the elastomer. Here, by dispersing a soft material in the elastomer, the film-forming property of the elastomer composition is improved, and further, the low-temperature hardness of the elastomer composition layer obtained by film-forming is reduced, and the resistance at low temperatures is reduced. Cracking properties can be greatly improved.

  Although it does not specifically limit as an elastomer used for the said elastomer layer, It is preferable to select from a known thermoplastic elastomer (TPE). Examples of the thermoplastic elastomer (TPE) include polystyrene-based thermoplastic elastomers, polyolefin-based thermoplastic elastomers, polydiene-based thermoplastic elastomers, polyvinyl chloride-based thermoplastic elastomers, chlorinated polyethylene-based thermoplastic elastomers, polyurethane-based thermoplastics. Examples include elastomers, polyester-based thermoplastic elastomers, polyamide-based thermoplastic elastomers, fluororesin-based thermoplastic elastomers, and among these, polyurethane-based thermoplastic elastomers (TPU) are preferable. In addition, these thermoplastic elastomers may be used individually by 1 type, and may be used in combination of 2 or more type.

  The above-mentioned polystyrene-based thermoplastic elastomer has an aromatic vinyl polymer block (hard segment) and a rubber block (soft segment), and the aromatic vinyl polymer portion forms a physical cross-link and becomes a crosslinking point. On the other hand, the rubber block imparts rubber elasticity. The polystyrene-based thermoplastic elastomer can be divided according to the arrangement pattern of the soft segments in the molecule. For example, styrene-butadiene-styrene block copolymer (SBS), styrene-isoprene-styrene block copolymer (SIS), Styrene-isobutylene-styrene block copolymer (SIBS), styrene-ethylene / butylene-styrene block copolymer (SEBS), styrene-ethylene / propylene-styrene block copolymer (SEPS), and the like. A block copolymer of crystalline polyethylene and ethylene / butylene-styrene random copolymer obtained by hydrogenating a block copolymer of polybutadiene and butadiene-styrene random copolymer, polybutadiene or ethylene-butadiene random Obtained by hydrogenating a block copolymer of the polymer and polystyrene, for example, also include diblock copolymer of crystalline polyethylene and polystyrene. Among these, styrene-isobutylene-styrene block copolymer (SIBS), styrene-ethylene from the balance of mechanical strength, heat stability, weather resistance, chemical resistance, gas barrier properties, flexibility, workability, etc. / Butylene-styrene block copolymer (SEBS) and styrene-ethylene / propylene-styrene block copolymer (SEPS) are preferred.

  The polyolefin-based thermoplastic elastomer includes a thermoplastic elastomer having a polyolefin block such as polypropylene or polyethylene as a hard segment and a rubber block such as an ethylene-propylene-diene copolymer as a soft segment. Such thermoplastic elastomer includes a blend type and an implant type. Examples of the polyolefin-based thermoplastic elastomer include maleic anhydride-modified ethylene-butene-1 copolymer, maleic anhydride-modified ethylene-propylene copolymer, halogenated butyl rubber, modified polypropylene, and modified polyethylene. You can also.

  Examples of the polydiene thermoplastic elastomer include 1,2-polybutadiene TPE, trans 1,4-polyisoprene TPE, hydrogenated conjugated diene TPE, and epoxidized natural rubber. The 1,2-polybutadiene-based TPE is a polybutadiene containing 90% or more of 1,2-bonds in the molecule, and is crystalline syndiotactic 1,2-polybutadiene as a hard segment and amorphous as a soft segment. It consists of 1,2-polybutadiene. Trans 1,4-polyisoprene-based TPE is polyisoprene having a trans 1,4 structure of 98% or more in the molecule, and includes crystalline trans 1,4 segments as hard segments and soft segments as soft segments. It consists of amorphous trans 1,4 segments.

  The polyvinyl chloride thermoplastic elastomer (TPVC) is generally roughly classified into the following three types.

(1) High molecular weight polyvinyl chloride (PVC) / plasticized polyvinyl chloride (PVC) blend type TPVC
It is a thermoplastic elastomer made of high molecular weight PVC for the hard segment and PVC plasticized with a plasticizer for the soft segment. In addition, by using high molecular weight PVC for the hard segment, the function of a crosslinking point is given to the microcrystal part.

(2) Partially cross-linked PVC / plasticized PVC blend type TPVC
It is a thermoplastic elastomer using PVC in which a partially crosslinked or branched structure is introduced into a hard segment and PVC plasticized with a plasticizer in a soft segment.

(3) PVC / elastomer alloy type TPVC
It is a thermoplastic elastomer that uses PVC for the hard segment and rubber such as partially crosslinked nitrile butadiene rubber (NBR) or TPE such as polyurethane TPE and polyester TPE for the soft segment.

  The chlorinated polyethylene-based thermoplastic elastomer is a soft resin obtained by reacting polyethylene with chlorine gas in a solvent such as an aqueous suspension or carbon tetrachloride. A chlorinated polyethylene (CPE) block is used for the segment. In the CPE block, both components of polyethylene and chlorinated polyethylene are mixed as a mixture having a multi-block or random structure.

  The polyester-based thermoplastic elastomer (TPEE) is a multi-block copolymer using polyester as a hard segment in a molecule and polyether or polyester having a low glass transition temperature (Tg) as a soft segment. TPEE can be divided into the following types according to the difference in molecular structure, and polyester / polyether type TPEE and polyester / polyester type TPEE dominate.

(1) Polyester / polyether type TPEE
Generally, it is a thermoplastic elastomer using aromatic crystalline polyester as a hard segment and polyether as a soft segment.

(2) Polyester / Polyester type TPEE
A thermoplastic elastomer using an aromatic crystalline polyester as a hard segment and an aliphatic polyester as a soft segment.

(3) Liquid crystalline TPEE
It is a thermoplastic elastomer using rigid liquid crystal molecules as hard segments and aliphatic polyester as soft segments.

  The polyamide-based thermoplastic elastomer (TPA) is a multi-block copolymer using polyamide as a hard segment and polyether or polyester having a low Tg as a soft segment. The polyamide component constituting the hard segment is selected from nylon 6, 66, 610, 11, 12 and the like, and nylon 6 and nylon 12 are mainly used. As the constituent material of the soft segment, a long-chain polyol such as polyether diol or polyester diol is used. Representative examples of polyether polyols include diol poly (oxytetramethylene) glycol (PTMG), poly (oxypropylene) glycol, and the like. Representative examples of polyester polyols include poly (ethylene adipate) glycol, poly (butylene- 1,4 adipate) glycol and the like.

  The fluororesin-based thermoplastic elastomer is an ABA type block copolymer made of fluororesin as a hard segment and fluororubber as a soft segment. Tetrafluoroethylene-ethylene copolymer or polyvinylidene fluoride (PVDF) is used for the fluororesin constituting the hard segment, and vinylidene fluoride-hexafluoropropylene-tetrafluoro is used for the fluororubber constituting the soft segment. An ethylene terpolymer or the like is used. More specifically, it includes vinylidene fluoride rubber, tetrafluoroethylene-propylene rubber, tetrafluoroethylene-perfluoromethyl vinyl ether rubber, phosphazene fluororubber, fluoropolyether, fluoronitroso rubber, perfluorotriazine. And the like. In addition, fluororesin TPE is microphase-separated like other TPE, and the hard segment forms the crosslinking point.

  The polyurethane-based thermoplastic elastomer (TPU) includes (1) a polyurethane obtained by a reaction of a short-chain glycol and an isocyanate as a hard segment, and (2) a polyurethane obtained by a reaction of a long-chain glycol and an isocyanate as a soft segment. Is a linear multi-block copolymer. Here, polyurethane is a general term for compounds having a urethane bond (—NHCOO—) obtained by polyaddition reaction (urethanization reaction) of isocyanate (—NCO) and alcohol (—OH). In the multilayer structure of the present invention, when the elastomer forming the elastomer layer is TPU, the stretchability and thermoformability can be improved by laminating the elastomer layer. Further, in such a multilayer structure, since the interlayer adhesion between the elastomer layer and the barrier layer can be improved, durability such as crack resistance is high, and even if the multilayer structure is deformed and used, gas barrier properties and stretchability are achieved. Can be maintained.

  The TPU is composed of a polymer polyol, an organic polyisocyanate, a chain extender and the like. The polymer polyol is a substance having a plurality of hydroxyl groups, and is obtained by polycondensation, addition polymerization (for example, ring-opening polymerization), polyaddition or the like. Examples of the polymer polyol include polyester polyol, polyether polyol, polycarbonate polyol, or a cocondensate thereof (for example, polyester-ether-polyol). Among these, polyester polyol or polycarbonate polyol is preferable, and polyester polyol is particularly preferable. In addition, these polymer polyols may be used individually by 1 type, and may be used in combination of 2 or more type.

  Here, the polyester polyol is, for example, according to a conventional method, a compound capable of forming an ester such as dicarboxylic acid, an ester thereof, or an anhydride thereof and a low molecular polyol are condensed by a direct esterification reaction or transesterification reaction, Alternatively, it can be produced by ring-opening polymerization of a lactone.

  It does not specifically limit as dicarboxylic acid which can be used for the production | generation of the said polyester polyol, The dicarboxylic acid generally used in manufacture of polyester is mentioned. Specific examples of the dicarboxylic acid include succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, dodecanedioic acid, methylsuccinic acid, 2-methylglutaric acid, trimethyladipic acid, 2- C4-C12 aliphatic dicarboxylic acids such as methyloctanedioic acid, 3,8-dimethyldecanedioic acid, 3,7-dimethyldecanedioic acid; cycloaliphatic dicarboxylic acids such as cyclohexanedicarboxylic acid; terephthalic acid, isophthalic acid Examples thereof include aromatic dicarboxylic acids such as acid, orthophthalic acid, and naphthalenedicarboxylic acid. These dicarboxylic acids may be used individually by 1 type, and 2 or more types may be mixed and used for them. Among these, an aliphatic dicarboxylic acid having 6 to 12 carbon atoms is preferable, and adipic acid, azelaic acid or sebacic acid is particularly preferable. These dicarboxylic acids have a carbonyl group that is more likely to react with a hydroxyl group, and can greatly improve the interlayer adhesion with the barrier layer.

  It does not specifically limit as a low molecular polyol which can be used for the production | generation of the said polyester polyol, The low molecular polyol generally used in manufacture of polyester is mentioned. Specific examples of the low molecular polyol include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, 1,3-propanediol, 2-methyl-1,3-propanediol, 1,3-butylene glycol, 1, 4-butanediol, neopentyl glycol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, 2-methyl-1,8-octane Diol, 2,7-dimethyl-1,8-octanediol, 1,9-nonanediol, 2-methyl-1,9-nonanediol, 1,10-decanediol, 2,2-diethyl-1,3- C2-C15 aliphatic diol such as propanediol; 1,4-cyclohexanediol, cyclo Cyclohexanedicarboxylic methanol, cyclooctane dimethanol, an alicyclic diol such as dimethyl cyclooctane dimethanol; 1,4-bis (beta-hydroxyethoxy) aromatic dihydric alcohols such as benzene. These low molecular polyols may be used alone or in a combination of two or more. Among these, 3-methyl-1,5-pentanediol, 2-methyl-1,8-octanediol, 2,7-dimethyl-1,8-octanediol, 1,9-nonanediol, 2,8- C5-C12 aliphatic diols having a methyl group in the side chain such as dimethyl-1,9-nonanediol are preferred. The polyester polyol obtained using such an aliphatic diol is likely to react with a hydroxyl group, and can greatly improve interlayer adhesion with the barrier layer. Further, a small amount of a trifunctional or higher functional low molecular polyol can be used in combination with the low molecular polyol. Examples of the trifunctional or higher functional low molecular polyol include trimethylolpropane, trimethylolethane, glycerin, 1,2,6-hexanetriol, and the like.

  Examples of the lactone that can be used to produce the polyester polyol include ε-caprolactone and β-methyl-δ-valerolactone.

  Examples of the polyether polyol include polyethylene glycol, polypropylene glycol, polytetramethylene glycol, poly (methyltetramethylene) glycol, and the like. These polyether polyols may be used individually by 1 type, and 2 or more types may be mixed and used for them. Among these, polytetramethylene glycol is preferable.

  Examples of the polycarbonate polyol include fats having 2 to 12 carbon atoms such as 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, and 1,10-decanediol. Preferred examples include compounds obtained by polycondensation of a group diol or a mixture thereof by the action of diphenyl carbonate or phosgene.

  The above polymer polyol preferably has a lower limit of the number average molecular weight of 500, more preferably 600, and even more preferably 700. On the other hand, the upper limit of the number average molecular weight of the polymer polyol is preferably 8,000, more preferably 5,000, and still more preferably 3,000. If the number average molecular weight of the polymer polyol is smaller than the above lower limit, the compatibility with the organic polyisocyanate is too high, and the elasticity of the resulting TPU becomes poor. Therefore, the mechanical properties such as stretchability of the resulting multilayer structure and heat There is a possibility that moldability may be lowered. On the other hand, if the number average molecular weight of the polymer polyol exceeds the above upper limit, the compatibility with the organic polyisocyanate is lowered, and mixing in the polymerization process becomes difficult. There is a possibility that a stable TPU cannot be obtained. In addition, the number average molecular weight of the polymer polyol is a number average molecular weight measured based on JIS-K-1577 and calculated based on the hydroxyl value.

  It does not specifically limit as said organic polyisocyanate, The well-known organic diisocyanate generally used for manufacture of TPU can be used. Examples of the organic diisocyanate include 4,4′-diphenylmethane diisocyanate, tolylene diisocyanate, phenylene diisocyanate, xylylene diisocyanate, 1,5-naphthylene diisocyanate, 3,3′-dichloro-4,4′-diphenylmethane diisocyanate, and toluic acid. Examples include aromatic diisocyanates such as diisocyanates; aliphatic or alicyclic diisocyanates such as hexamethylene diisocyanate, isophorone diisocyanate, 4,4′-dicyclohexylmethane diisocyanate, and hydrogenated xylylene diisocyanate. Among these, 4,4'-diphenylmethane diisocyanate is preferable from the viewpoint of improving the strength and flex resistance of the resulting multilayer structure. These organic polyisocyanates may be used alone or in combination of two or more.

  The chain extender is not particularly limited, and a known chain extender generally used in the production of TPU can be used, and the molecular weight is 300 having two or more active hydrogen atoms capable of reacting with an isocyanate group in the molecule. The following low molecular weight compounds are preferably used. Examples of the chain extender include ethylene glycol, propylene glycol, 1,4-butanediol, 1,6-hexanediol, 1,4-bis (β-hydroxyethoxy) benzene, 1,4-cyclohexanediol, and the like. . Among these, 1,4-butanediol is particularly preferable from the viewpoint of further improving the stretchability and thermoformability of the resulting multilayer structure. These chain extenders may be used individually by 1 type, and 2 or more types may be mixed and used for them.

  Examples of the TPU production method include production methods using the above-mentioned polymer polyol, organic polyisocyanate, and chain extender and utilizing a known urethanization reaction technique, and using either the prepolymer method or the one-shot method. May be. In particular, it is preferable to perform melt polymerization in the substantial absence of a solvent, and it is more preferable to perform continuous melt polymerization using a multi-screw extruder.

  In the TPU, the ratio of the mass of the organic polyisocyanate to the total mass of the polymer polyol and the chain extender [isocyanate / (polymer polyol + chain extender)] is preferably 1.02 or less. When the ratio exceeds 1.02, long-term operation stability during molding may be deteriorated.

  The soft material used for the elastomer layer preferably has a Young's modulus at 23 ° C. lower than that of the elastomer used for the elastomer layer, preferably 1000 MPa or less, and more preferably in the range of 0.01 to 500 MPa. If the Young's modulus at 23 ° C. of the soft material is higher than that of the elastomer, the effect exhibited by the dispersion of the soft material cannot be obtained, and crack resistance may be lowered. The elastomer used for the elastomer layer usually has a Young's modulus at 23 ° C. of 10 MPa or more, but is preferably in the range of 20 to 100 MPa.

  The soft material is preferably a compound having a functional group capable of reacting with a hydroxyl group. When the soft material has a functional group capable of reacting with a hydroxyl group, the soft material is uniformly dispersed in the elastomer, and the average particle diameter of the soft material can be reduced. Here, functional groups capable of reacting with hydroxyl groups include hydroxyl groups, carboxyl groups, carboxylate groups, isocyanate groups, isothiocyanate groups, epoxy groups, amino groups, boron-containing groups, maleic acid, maleic anhydride, and alkoxysilanes. And a functional group introduced by modification with a compound selected from the group consisting of. Here, the functional group is not limited to those capable of directly reacting with the elastomer molecule or having a high affinity, and includes examples in which the functional group can react with the elastomer molecule by pre-reaction with another agent. The soft material may have two or more of such functional groups.

Examples of the boron-containing group include a boron-containing group that can be converted to a boronic acid group in the presence of a boronic acid group or water. Among the boron-containing groups, the boronic acid group is represented by the following formula (4).

The boron-containing group that can be converted to a boronic acid group in the presence of water refers to a boron-containing group that can be converted to a boronic acid group represented by the above formula (4) by hydrolysis in the presence of water. . More specifically, water alone, a mixture of water and an organic solvent (toluene, xylene, acetone, etc.), a mixture of a 5% boric acid aqueous solution and the organic solvent, and the like, at room temperature to 150 ° C. It means a functional group that can be converted to a boronic acid group when hydrolyzed for 10 minutes to 2 hours. Representative examples of such functional groups include boronic acid ester groups represented by the following formula (5), boronic acid anhydride groups represented by the following formula (6), boronic acid groups represented by the following formula (7), etc. Is mentioned.

Here, X and Y are a hydrogen atom, an aliphatic hydrocarbon group (a linear or branched alkyl group having 1 to 20 carbon atoms, or an alkenyl group), an alicyclic hydrocarbon group (a cycloalkyl group, a cycloalkenyl group). Group) and an aromatic hydrocarbon group (phenyl group, biphenyl group, etc.), and X and Y may be the same or different. However, the case where both X and Y are hydrogen atoms is excluded. X and Y may be bonded. R ¹ , R ² and R ³ represent the same hydrogen atom, aliphatic hydrocarbon group, alicyclic hydrocarbon group and aromatic hydrocarbon group as those of X and Y, and R ¹ , R ² and R ³ May be the same or different. M represents an alkali metal. Further, the above X, Y, R ¹ , R ² and R ³ may have other groups such as a hydroxyl group, a carboxyl group, a halogen atom and the like.

  Specific examples of the boronic acid ester group represented by the formula (5) include boronic acid dimethyl ester group, boronic acid diethyl ester group, boronic acid dibutyl ester group, boronic acid dicyclohexyl ester group, boronic acid ethylene glycol ester group, boron Propylene glycol ester group, boronic acid 1,3-propanediol ester group, boronic acid 1,3-butanediol ester group, boronic acid neopentyl glycol ester group, boronic acid catechol ester group, boronic acid glycerin ester group, boronic acid Examples thereof include a trimethylol ethane ester group, a boronic acid trimethylol propane ester group, and a boronic acid diethanolamine ester group.

  Moreover, as a boronic acid base shown by the said Formula (7), the alkali metal base of boronic acid, etc. are mentioned. Specific examples include sodium boronate base and potassium boronate base.

  Among such boron-containing groups, a boronic acid cyclic ester group is preferable from the viewpoint of thermal stability. Examples of the boronic acid cyclic ester group include a boronic acid cyclic ester group containing a 5-membered ring or a 6-membered ring. Specific examples include a boronic acid ethylene glycol ester group, a boronic acid propylene glycol ester group, a boronic acid 1,3-propanediol ester group, a boronic acid 1,3-butanediol ester group, and a boronic acid glycerin ester group. .

  The soft material is preferably a compound having a molecular weight of 10,000 or less, more preferably a compound having a molecular weight of 5,000 or less, more preferably a compound having a molecular weight of 2,000 or less, and particularly preferably a molecular weight. Is a compound having 1,000 or less. When the molecular weight of the soft material is within the above range, the soft material is uniformly dispersed in the elastomer, and the film-forming property of the elastomer composition can be improved. Further, from the viewpoint of enhancing the entanglement with the elastomer and improving the crack resistance, the molecular weight of the soft material is preferably 750 or more. In addition, when the said soft material is a polymer, the molecular weight of this soft material refers to the weight average molecular weight of polystyrene conversion measured by gel permeation chromatography (GPC).

  The soft material is preferably in a state where it does not cause inconvenient separation (exudation, bloom, etc.) in the elastomer composition and is homogeneously mixed, so that the soft material is compatible with the elastomer. It is preferable.

  The soft materials include butadiene rubber (BR), isoprene rubber (IR), styrene-butadiene copolymer rubber (SBR), natural rubber (NR), butyl rubber (IIR), and isobutylene, particularly from the viewpoint of improving crack resistance. -P-methylstyrene, chlorosulfonated polyethylene rubber (CSM), ethylene propylene rubber (EPM, EPDM), ethylene-butene rubber, ethylene-octene rubber, chloroprene rubber (CR), acrylic rubber (ACM), nitrile rubber (NBR), In addition to rubbers such as silicone rubber, these hydrogenated rubbers (for example, hydrogenated SBR), modified rubbers (for example, modified natural rubber, brominated-butyl rubber (Br-IIR), chlorinated butyl rubber (Cl-IIR), bromine Isobutylene-p-methylstyrene, etc.), liquid rubber (ie low molecular weight) Beam), or the like can be used. From the same viewpoint, the soft material includes polyethylene (PE), polypropylene (PP), ethylene-butene copolymer, styrene-ethylene-butene-styrene block copolymer (SEBS), styrene-ethylene-propylene. In addition to polymers such as styrene block copolymer (SEPS), styrene-isobutylene-chloromethylstyrene block copolymer, polyamide, etc., these hydrogenated products, modified products, and the like can be used. More specifically, maleic anhydride-modified hydrogenated styrene-ethylene-butadiene-styrene block copolymer, maleic anhydride-modified ultra-low density polyethylene and the like can be mentioned. In addition, these soft materials may be used individually by 1 type, and may blend and use 2 or more types.

  Moreover, you may use a known plasticizer as said soft material from a viewpoint which is excellent in compatibility with an elastomer and reduces a glass transition point (Tg). Here, as the plasticizer, phthalic acid plasticizers such as dibutyl phthalate, diheptyl phthalate, dioctyl phthalate (DOP), ditridecyl phthalate, and trioctyl melylate; phosphates such as tricresyl phosphate and trioctyl phosphate Plasticizers; fatty acid plasticizers such as tributyl citrate, dioctyl adipate, dioctyl sebacate, and methylacetyl ricinolate; epoxy plasticizers such as epoxidized soybean oil and diisodecyl-4,5-epoxyterolahydrophthalate; N-butyl In addition to amide plasticizers such as benzenesulfonamide, chlorinated paraffin, sunflower oil suitable for diene elastomer, and the like can be mentioned. In addition, these soft materials may be used individually by 1 type, and may blend and use 2 or more types.

  It is preferable that the content rate of the soft material in the said elastomer composition is 10-30 mass%. If the content of the soft material is less than 10% by mass, the effect of improving film formability and crack resistance may not be sufficiently obtained, and the low temperature hardness of the elastomer layer may not be sufficiently reduced. On the other hand, if the content of the soft material exceeds 30% by mass, the content of the soft material is excessively increased, and the film formability may be lowered.

  You may mix | blend a radical crosslinking agent with the said elastomer composition. When an elastomer composition contains a radical crosslinking agent, the crosslinking effect at the time of active energy ray irradiation can be improved, and the interlayer adhesiveness of a laminated body can further be improved. Moreover, it is also possible to reduce the irradiation amount of an active energy ray compared with the case where a radical crosslinking agent does not exist in an elastomer composition. The content of the radical crosslinking agent in the elastomer composition is preferably from 0.01 to 10% by mass, more preferably from 0.05 to 9% by mass, from the viewpoint of a balance between the crosslinking effect and economy, and 0.1 to 8%. More preferred is mass%. Examples of the radical crosslinking agent include trimethylolpropane trimethacrylate, triallyl isocyanurate, triallyl cyanurate, diethylene glycol diacrylate, neophenylene glycol diacrylate, and the like. In addition, these radical crosslinking agents may be used individually by 1 type, and may be used in combination of 2 or more type.

  In addition to the elastomer, soft material, and radical crosslinking agent, the elastomer composition contains a wide variety of additives such as metal salts, heat stabilizers, ultraviolet absorbers, antioxidants, colorants, and fillers described below. They can be appropriately selected and blended within a range that does not impair the object of the present invention. In addition, the content of additives other than the elastomer in the elastomer composition is preferably 50% by mass or less, more preferably 30% by mass or less, and still more preferably 10% by mass or less.

The elastomer composition has a melt viscosity (η _1B ) of 1 × 10 ² Pa · s to 1 × 10 ⁴ Pa · s at a temperature of 210 ° C. and a shear rate of 10 / sec, a temperature of 210 ° C. and a shear rate of 1 The melt viscosity (η _2B ) at 1,000 / second is 1 × 10 ¹ Pa · s or more and 1 × 10 ³ Pa · s or less, and the melt viscosity ratio (η _2B / η _1B ) is expressed by the following formula ( It is preferable to satisfy 1B).
−0.8 ≦ (1/2) log ₁₀ (η _2B / η _1B ) ≦ −0.1 (1B)

If the melt viscosity (η _1B ) is less than 1 × 10 ² Pa · s, neck-in and film shaking will become significant during extrusion film formation by melt coextrusion lamination or melt extrusion, and the resulting laminate or elastomer layer before lamination As a result, the thickness unevenness and the reduction of the width become large, and it may not be possible to obtain a laminated body having a uniform and target size. On the other hand, when the melt viscosity (η _1B ) exceeds 1 × 10 ⁴ Pa · s, film breakage is likely to occur particularly when performing melt coextrusion lamination or melt extrusion molding under high-speed take-up conditions exceeding 100 m / min. Thus, the high-speed film forming property is remarkably impaired, and die swell is likely to occur, which may make it difficult to obtain a thin laminate or an elastomer layer before lamination.

In addition, when the melt viscosity (η _2B ) is less than 1 × 10 ¹ Pa · s, neck-in and film shake become remarkable during extrusion film formation by melt coextrusion lamination or melt extrusion, and the resulting multilayer structure or There is a possibility that the thickness variation and the width reduction of the elastomer layer before lamination are increased. On the other hand, if the melt viscosity (η _2B ) exceeds 1 × 10 ³ Pa · s, the torque applied to the extruder becomes too high, and extrusion spots and weld lines may easily occur.

When the value of (1/2) log ₁₀ (η _2B / η _1B ) calculated from the melt viscosity ratio (η _2B / η _1B ) is less than −0.8, extrusion by melt coextrusion lamination or melt extrusion There is a possibility that film breakage is likely to occur during film formation and high-speed film formation is impaired. On the other hand, when the value of (1/2) log ₁₀ (η _2B / η _1B ) exceeds −0.1, neck-in or film swaying occurs at the time of extrusion film formation by melt coextrusion lamination or melt extrusion. There is a possibility that thickness unevenness or width reduction may occur in the laminate or the elastomer layer before lamination. From this viewpoint, the value of (1/2) log ₁₀ (η _2B / η _1B ) is more preferably −0.6 or more, and more preferably −0.2 or less. In addition, the value of (1/2) log ₁₀ (η _2B / η _1B ) in the above formula is the melt viscosity (η _1B ) and the melt in the logarithmic logarithmic graph with the melt viscosity as the vertical axis and the shear rate as the horizontal axis. It is determined as the slope of a straight line connecting two points of viscosity (η _2B ).

The above elastomer composition has a viscosity behavior stability (M ₁₀₀ / M ₂₀ , where M ₂₀ is 20 minutes from the start of kneading) in relation to the melt kneading time and torque at at least one point at a temperature 10 to 80 ° C. higher than the melting point of the elastomer. torque after, M ₁₀₀ is preferably a value of representing the torque after 100 minutes from the start kneading) is in the range of 0.5 to 1.5. The viscosity behavior stability value closer to 1 indicates that the viscosity change is smaller and the thermal stability (long run property) is more excellent.

The elastomer layer constituting the laminate preferably has an air permeability of 3.0 × 10 ⁻⁸ cm ³ · cm / cm ² · sec · cmHg or less at 20 ° C. and 65% RH. The air permeability is measured according to JIS K7126-1: 2006 (isobaric method).

  The barrier layer constituting the laminate is a layer for imparting gas barrier properties to the laminate, and is a layer made of a resin composition in which a resin exists as a matrix. The Young's modulus at 23 ° C. in the resin A layer made of a resin composition in which a lower soft material is dispersed is more preferable. The matrix means a continuous phase. Moreover, this resin composition may be comprised only from resin. Here, by dispersing the soft material in the resin, the elastic modulus of the resin composition can be lowered, and durability such as crack resistance can be improved.

The barrier layer preferably has an air permeability at 20 ° C. and 65% RH of 3.0 × 10 ⁻¹² cm ³ · cm / cm ² · sec · cmHg or less, and 1.0 × 10 More preferably, it is ^-12 cm ³ · cm / cm ² · sec · cm Hg or less. The air permeability is measured according to JIS K7126-1: 2006 (isobaric method).

  The resin used for the barrier layer is not particularly limited, but an ethylene-vinyl alcohol copolymer (EVOH), a modified ethylene-vinyl alcohol copolymer (modified EVOH), a polyamide resin, a polyvinylidene chloride resin ( PVDC), polyethylene terephthalate (PET), polyacrylonitrile and the like. Among these, ethylene-vinyl alcohol copolymer (EVOH) and modified ethylene-vinyl alcohol copolymer (modified EVOH) are preferable. The modified EVOH is a compound obtained by, for example, reacting an epoxy compound or the like with EVOH, and has a lower elastic modulus than ordinary EVOH. For this reason, the elasticity modulus of a barrier layer can be reduced and durability, such as crack resistance, can also be improved. In addition, these resin may be used individually by 1 type, and may be used in combination of 2 or more type.

  From the viewpoint of improving the gas barrier property, melt moldability and interlayer adhesion of the laminate, the ethylene-vinyl alcohol copolymer preferably has an ethylene content of 3 to 70 mol%, preferably 10 to 60 mol%. More preferably, it is more preferably 20 to 55 mol%, and particularly preferably 25 to 50 mol%. If the ethylene content is less than 3 mol%, the water resistance, hot water resistance, gas barrier property and melt moldability under high humidity of the laminate may be deteriorated. May decrease.

  The ethylene-vinyl alcohol copolymer preferably has a saponification degree of 80% or more, and more preferably 90% or more, from the viewpoint of improving gas barrier properties, moisture resistance and interlayer adhesion of the laminate. Is more preferably 95% or more, and particularly preferably 99% or more. On the other hand, the saponification degree of the ethylene-vinyl alcohol copolymer is preferably 99.99% or less. If the saponification degree of EVOH is less than 80%, the melt moldability, gas barrier property, coloration resistance and moisture resistance of the laminate may be lowered.

  From the viewpoint of obtaining gas barrier properties, flex resistance and fatigue resistance, the ethylene-vinyl alcohol copolymer has a melt flow rate (MFR) of 0.1 to 30 g / 10 min under a load of 190 ° C. and 21.18 N. It is preferable that it is 0.3 to 25 g / 10 min.

The ethylene-vinyl alcohol copolymer has a 1,2-glycol bond structural unit content G (mol%) of the following formula:
G ≦ 1.58−0.0244 × E
[Wherein, G is the content (mol%) of 1,2-glycol bond structural unit, E is the ethylene unit content (mol%) in EVOH, where E ≦ 64) And the intrinsic viscosity is preferably in the range of 0.05 to 0.2 L / g. By using such EVOH, the obtained laminate is less dependent on the humidity of the gas barrier property, has good transparency and gloss, and can be easily laminated on other resin layers. The content of the 1,2-glycol-bonded structural unit was determined by changing the EVOH sample to a dimethyl sulfoxide solution according to the method described in “S. Aniya et al., Analytical Science Vol. 1, 91 (1985)”. It can be measured by nuclear magnetic resonance at 90 ° C.

  The modified ethylene-vinyl alcohol copolymer has, in addition to ethylene units and vinyl alcohol units, other repeating units (hereinafter also referred to as structural units), for example, one or more kinds of repeating units derived from these units. It is a polymer. The preferred ethylene content, degree of saponification, melt flow rate (MFR), content of 1,2-glycol bond structural unit and intrinsic viscosity of the modified EVOH are the same as those of the above-mentioned EVOH.

The modified EVOH preferably has at least one structural unit selected from the structural units (8) and (9) shown below, for example, and the structural unit is contained in a proportion of 0.5 to 30 mol% with respect to the total structural units. It is more preferable to contain. Such a modified EVOH can improve the flexibility and processing characteristics of the resin or resin composition, and the interlayer adhesion, stretchability, and thermoformability of the multilayer structure.

In said formula (8), R < ⁴ >, R < ⁵ > and R < ⁶ > are respectively independently a hydrogen atom, a C1-C10 aliphatic hydrocarbon group, a C3-C10 alicyclic hydrocarbon group, An aromatic hydrocarbon group or a hydroxyl group having 6 to 10 carbon atoms is represented. In addition, a pair of R ⁴ , R ⁵ and R ⁶ may be bonded (except when a pair of R ⁴ , R ⁵ and R ⁶ are both hydrogen atoms). In addition, the aliphatic hydrocarbon group having 1 to 10 carbon atoms, the alicyclic hydrocarbon group having 3 to 10 carbon atoms, or the aromatic hydrocarbon group having 6 to 10 carbon atoms has a hydroxyl group, a carboxy group, or a halogen atom. You may do it. On the other hand, in the above formula ^{(9), R 7, R} 8, R 9 and R ¹⁰ are each independently a hydrogen atom, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, alicyclic of 3 to 10 carbon atoms A formula hydrocarbon group, a C6-C10 aromatic hydrocarbon group, or a hydroxyl group is represented. R ⁷ and R ⁸ or R ⁹ and R ¹⁰ may be bonded (except when R ⁷ and R ⁸ or R ⁹ and R ¹⁰ are both hydrogen atoms). The aliphatic hydrocarbon group having 1 to 10 carbon atoms, the alicyclic hydrocarbon group having 3 to 10 carbon atoms, or the aromatic hydrocarbon group having 6 to 10 carbon atoms is a hydroxyl group, an alkoxy group, a carboxy group, or a halogen atom. You may have an atom.

  In the modified EVOH, the lower limit of the content of the structural unit (8) and / or (9) with respect to all the structural units is preferably 0.5 mol%, more preferably 1 mol%, further 1.5 mol%. preferable. On the other hand, in the modified EVOH, the upper limit of the content of the structural unit (8) and / or (9) with respect to all the structural units is preferably 30 mol%, more preferably 15 mol%, still more preferably 10 mol%. By containing the structural unit (8) and / or (9) in the above proportion, the flexibility and processing characteristics of the resin composition, and the interlayer adhesion, stretchability and thermoformability of the laminate can be improved. it can.

  In the structural units (8) and (9), examples of the aliphatic hydrocarbon group having 1 to 10 carbon atoms include an alkyl group and an alkenyl group, and examples of the alicyclic hydrocarbon group having 3 to 10 carbon atoms include cyclo An alkyl group, a cycloalkenyl group, etc. are mentioned, A phenyl group etc. are mentioned as a C6-C10 aromatic hydrocarbon group.

In the structural unit (8), R ⁴ , R ⁵ and R ⁶ are preferably each independently a hydrogen atom, a methyl group, an ethyl group, a hydroxyl group, a hydroxymethyl group or a hydroxyethyl group. More preferably, they are each independently a hydrogen atom, a methyl group, a hydroxyl group or a hydroxymethyl group. With such R ⁴ , R ⁵ and R ⁶ , the stretchability and thermoformability of the laminate can be further improved.

  The method of incorporating the structural unit (8) in EVOH is not particularly limited. For example, in the copolymerization of ethylene and vinyl ester, a monomer further derived into the structural unit (8). And the like. Examples of the monomer derived from the structural unit (8) include alkene such as propylene, butylene, pentene, hexene; 3-hydroxy-1-propene, 3-acyloxy-1-propene, 3-acyloxy-1 -Butene, 4-acyloxy-1-butene, 3,4-diacyloxy-1-butene, 3-acyloxy-4-hydroxy-1-butene, 4-acyloxy-3-hydroxy-1-butene, 3-acyloxy-4 -Methyl-1-butene, 4-acyloxy-2-methyl-1-butene, 4-acyloxy-3-methyl-1-butene, 3,4-diacyloxy-2-methyl-1-butene, 4-hydroxy-1 -Pentene, 5-hydroxy-1-pentene, 4,5-dihydroxy-1-pentene, 4-acyloxy-1-pentene, 5-acyloxy-1-pentene, , 5-diacyloxy-1-pentene, 4-hydroxy-3-methyl-1-pentene, 5-hydroxy-3-methyl-1-pentene, 4,5-dihydroxy-3-methyl-1-pentene, 5,6 -Dihydroxy-1-hexene, 4-hydroxy-1-hexene, 5-hydroxy-1-hexene, 6-hydroxy-1-hexene, 4-acyloxy-1-hexene, 5-acyloxy-1-hexene, 6-acyloxy Alkenes having a hydroxyl group or an ester group such as -1-hexene and 5,6-diacyloxy-1-hexene are exemplified. Among these, from the viewpoint of copolymerization reactivity and gas barrier properties of the resulting laminate, propylene, 3-acyloxy-1-propene, 3-acyloxy-1-butene, 4-acyloxy-1-butene, and 3, 4-diacetoxy-1-butene is preferred. Specifically, propylene, 3-acetoxy-1-propene, 3-acetoxy-1-butene, 4-acetoxy-1-butene, and 3,4-diacetoxy-1-butene are more preferable, and 3,4-diacetoxy- 1-butene is particularly preferred. In addition, when using the alkene which has ester, it is induced | guided | derived to the said structural unit (8) in the case of a saponification reaction.

In the structural unit (9), R ⁷ and R ⁸ are preferably both hydrogen atoms. In particular, it is more preferable that R ⁷ and R ⁸ are both hydrogen atoms, one of R ⁹ and R ¹⁰ is an aliphatic hydrocarbon group having 1 to 10 carbon atoms, and the other is a hydrogen atom. The aliphatic hydrocarbon group in the structural unit (9) is preferably an alkyl group or an alkenyl group. Further, from the viewpoint of particularly emphasizing the gas barrier property of the multilayer structure, it is preferable that one of R ⁹ and R ¹⁰ is a methyl group or an ethyl group, and the other is a hydrogen atom. Furthermore, it is also preferred that one of R ⁹ and R ¹⁰ is a substituent represented by (CH ₂ ) _h OH (where h is an integer of 1 to 8) and the other is a hydrogen atom. In the substituent represented by (CH ₂ ) _h OH, h is preferably an integer of 1 to 4, more preferably 1 or 2, and particularly preferably 1.

In addition, the method of incorporating the structural unit (9) in EVOH is not particularly limited, and examples thereof include a method of reacting EVOH obtained by a saponification reaction with a monovalent epoxy compound. Here, preferred examples of the monovalent epoxy compound include compounds represented by the following formulas (10) to (16).

In said formula (10)-(16), R < ¹¹ >, R < ¹² >, R <^13> , R <^14> and R < ¹⁵ > are a hydrogen atom, a C1-C10 aliphatic hydrocarbon group (an alkyl group or an alkenyl group etc.), An alicyclic hydrocarbon group having 3 to 10 carbon atoms (such as a cycloalkyl group or a cycloalkenyl group) or an aromatic hydrocarbon group having 6 to 10 carbon atoms (such as a phenyl group) is represented. R ¹¹ and R ¹² or R ¹⁴ and R ¹⁵ may be the same or different. Moreover, i, j, k, p, and q represent the integer of 1-8.

  Examples of the monovalent epoxy compound represented by the formula (10) include epoxy ethane (ethylene oxide), epoxy propane, 1,2-epoxybutane, 2,3-epoxybutane, and 3-methyl-1,2- Epoxybutane, 1,2-epoxypentane, 2,3-epoxypentane, 3-methyl-1,2-epoxypentane, 4-methyl-1,2-epoxypentane, 4-methyl-2,3-epoxypentane, 3-ethyl-1,2-epoxypentane, 1,2-epoxyhexane, 2,3-epoxyhexane, 3,4-epoxyhexane, 3-methyl-1,2-epoxyhexane, 4-methyl-1,2 -Epoxyhexane, 5-methyl-1,2-epoxyhexane, 3-ethyl-1,2-epoxyhexane, 3-propyl-1,2-epoxy Sun, 4-ethyl-1,2-epoxyhexane, 5-methyl-1,2-epoxyhexane, 4-methyl-2,3-epoxyhexane, 4-ethyl-2,3-epoxyhexane, 2-methyl- 3,4-epoxyhexane, 2,5-dimethyl-3,4-epoxyhexane, 3-methyl-1,2-epoxyheptane, 4-methyl-1,2-epoxyhexane, 5-methyl-1,2- Epoxyheptane, 6-methyl-1,2-epoxyheptane, 3-ethyl-1,2-epoxyheptane, 3-propyl-1,2-epoxyheptane, 3-butyl-1,2-epoxyheptane, 4-ethyl -1,2-epoxyheptane, 4-propyl-1,2-epoxyheptane, 6-ethyl-1,2-epoxyheptane, 4-methyl-2,3-epoxyheptane, 4 Ethyl-2,3-epoxyheptane, 4-propyl-2,3-epoxyheptane, 2-methyl-3,4-epoxyheptane, 5-methyl-3,4-epoxyheptane, 5-ethyl-3,4- Epoxyheptane, 2,5-dimethyl-3,4-epoxyheptane, 2-methyl-5-ethyl-3,4-epoxyheptane, 1,2-epoxyheptane, 2,3-epoxyheptane, 3,4-epoxy Heptane, 1,2-epoxyoctane, 2,3-epoxyoctane, 3,4-epoxyoctane, 4,5-epoxyoctane, 1,2-epoxynonane, 2,3-epoxynonane, 3,4-epoxynonane 4,5-epoxynonane, 1,2-epoxydecane, 2,3-epoxydecane, 3,4-epoxydecane, 4,5-epoxydecane, 5,6-d Poxydecane, 1,2-epoxyundecane, 2,3-epoxyundecane, 3,4-epoxyundecane, 4,5-epoxyundecane, 5,6-epoxyundecane, 1,2-epoxydodecane, 2,3-epoxydodecane 3,4-epoxydodecane, 4,5-epoxydodecane, 5,6-epoxydodecane, 6,7-epoxydodecane, epoxyethylbenzene, 1-phenyl-1,2-propane, 3-phenyl-1,2- Epoxypropane, 1-phenyl-1,2-epoxybutane, 3-phenyl-1,2-epoxypentane, 4-phenyl-1,2-epoxypentane, 5-phenyl-1,2-epoxypentane, 1-phenyl -1,2-epoxyhexane, 3-phenyl-1,2-epoxyhexane, 4-phenyl-1,2- Pokishihekisan, 5-phenyl-1,2-epoxy hexane, 6-phenyl-1,2-epoxy hexane, and the like.

  Examples of the monovalent epoxy compound represented by the above formula (11) include methyl glycidyl ether, ethyl glycidyl ether, n-propyl glycidyl ether, isopropyl glycidyl ether, n-butyl glycidyl ether, isobutyl glycidyl ether, tert-butyl glycidyl. Ether, 1,2-epoxy-3-pentyloxypropane, 1,2-epoxy-3-hexyloxypropane, 1,2-epoxy-3-heptyloxypropane, 1,2-epoxy-4-phenoxybutane, , 2-epoxy-4-benzyloxybutane, 1,2-epoxy-5-methoxypentane, 1,2-epoxy-5-ethoxypentane, 1,2-epoxy-5-propoxypentane, 1,2-epoxy- 5-butoxypentane, 1,2-d Xyl-5-pentyloxypentane, 1,2-epoxy-5-hexyloxypentane, 1,2-epoxy-5-phenoxypentane, 1,2-epoxy-6-methoxyhexane, 1,2-epoxy-6 Ethoxyhexane, 1,2-epoxy-6-propoxyhexane, 1,2-epoxy-6-butoxyhexane, 1,2-epoxy-6-heptyloxyhexane, 1,2-epoxy-7-methoxyheptane, 1, 2-epoxy-7-ethoxyheptane, 1,2-epoxy-7-propoxyheptane, 1,2-epoxy-7-butoxyheptane, 1,2-epoxy-8-methoxyoctane, 1,2-epoxy-8- Ethoxyoctane, 1,2-epoxy-8-butoxyoctane, glycidol, 3,4-epoxy-1-butanol, 4, -Epoxy-1-pentanol, 5,6-epoxy-1-hexanol, 6,7-epoxy-1-heptanol, 7,8-epoxy-1-octanol, 8,9-epoxy-1-nonanol, 9, Examples include 10-epoxy-1-decanol, 10,11-epoxy-1-undecanol, and the like.

  Examples of the monovalent epoxy compound represented by the formula (12) include ethylene glycol monoglycidyl ether, propanediol monoglycidyl ether, butanediol monoglycidyl ether, pentanediol monoglycidyl ether, hexanediol monoglycidyl ether, heptanediol. Examples thereof include monoglycidyl ether and octanediol monoglycidyl ether.

  Examples of the monovalent epoxy compound represented by the formula (13) include 3- (2,3-epoxy) propoxy-1-propene, 4- (2,3-epoxy) propoxy-1-butene, 5- (2,3-epoxy) propoxy-1-pentene, 6- (2,3-epoxy) propoxy-1-hexene, 7- (2,3-epoxy) propoxy-1-heptene, 8- (2,3- Epoxy) propoxy-1-octene and the like.

  Examples of the monovalent epoxy compound represented by the formula (14) include 3,4-epoxy-2-butanol, 2,3-epoxy-1-butanol, 3,4-epoxy-2-pentanol, 2 , 3-epoxy-1-pentanol, 1,2-epoxy-3-pentanol, 2,3-epoxy-4-methyl-1-pentanol, 2,3-epoxy-4,4-dimethyl-1- Pentanol, 2,3-epoxy-1-hexanol, 3,4-epoxy-2-hexanol, 4,5-epoxy-3-hexanol, 1,2-epoxy-3-hexanol, 2,3-epoxy-4 , 4-dimethyl-1-hexanol, 2,3-epoxy-4,4-diethyl-1-hexanol, 2,3-epoxy-4-methyl-4-ethyl-1-hexanol, 3,4-epoxy 5-methyl-2-hexanol, 3,4-epoxy-5,5-dimethyl-2-hexanol, 3,4-epoxy-2-heptanol, 2,3-epoxy-1-heptanol, 4,5-epoxy- 3-heptanol, 2,3-epoxy-4-heptanol, 1,2-epoxy-3-heptanol, 2,3-epoxy-1-octanol, 3,4-epoxy-2-octanol, 4,5-epoxy- 3-octanol, 5,6-epoxy-4-octanol, 2,3-epoxy-4-octanol, 1,2-epoxy-3-octanol, 2,3-epoxy-1-nonanol, 3,4-epoxy- 2-nonanol, 4,5-epoxy-3-nonanol, 5,6-epoxy-4-nonanol, 3,4-epoxy-5-nonanol, 2,3-epoxy -4-nonanol, 1,2-epoxy-3-nonanol, 2,3-epoxy-1-decanol, 3,4-epoxy-2-decanol, 4,5-epoxy-3-decanol, 5,6-epoxy -4-decanol, 6,7-epoxy-5-decanol, 3,4-epoxy-5-decanol, 2,3-epoxy-4-decanol, 1,2-epoxy-3-decanol and the like.

  Examples of the monovalent epoxy compound represented by the formula (15) include 1,2-epoxycyclopentane, 1,2-epoxycyclohexane, 1,2-epoxycycloheptane, 1,2-epoxycyclooctane, , 2-epoxycyclononane, 1,2-epoxycyclodecane, 1,2-epoxycycloundecane, 1,2-epoxycyclododecane and the like.

  Examples of the monovalent epoxy compound represented by the above formula (16) include 3,4-epoxycyclopentene, 3,4-epoxycyclohexene, 3,4-epoxycycloheptene, 3,4-epoxycyclooctene, 3 , 4-epoxycyclononene, 1,2-epoxycyclodecene, 1,2-epoxycycloundecene, 1,2-epoxycyclododecene, and the like.

  Among the monovalent epoxy compounds, epoxy compounds having 2 to 8 carbon atoms are preferable. In particular, from the viewpoint of easy handling of the compound and reactivity with respect to EVOH, the carbon number of the monovalent epoxy compound is more preferably 2 to 6, and further preferably 2 to 4. The monovalent epoxy compound is particularly preferably a compound represented by the formula (10) or (11) among the compounds represented by these formulas. Specifically, 1,2-epoxybutane, 2,3-epoxybutane, epoxypropane, epoxyethane, and glycidol are preferable from the viewpoints of reactivity to EVOH and gas barrier properties of the resulting laminate, and among these, epoxypropane And glycidol are particularly preferred.

  In the present invention, the ethylene-vinyl alcohol copolymer is obtained, for example, by polymerizing ethylene and a vinyl ester to obtain an ethylene-vinyl ester copolymer, and saponifying the ethylene-vinyl ester copolymer. . Further, the modified ethylene-vinyl alcohol copolymer, as described above, (i) in the polymerization of ethylene and vinyl ester, further copolymerized monomers derived from the structural unit (8), (ii) It is obtained by reacting a monovalent epoxy compound with EVOH obtained by a saponification reaction. Here, the polymerization method of the ethylene-vinyl alcohol copolymer and the modified ethylene-vinyl alcohol copolymer is not particularly limited, and for example, any of solution polymerization, suspension polymerization, emulsion polymerization, and bulk polymerization may be used. Moreover, any of a continuous type and a batch type may be sufficient.

  Examples of the vinyl ester that can be used for the polymerization include vinyl acetate, vinyl propionate, and vinyl pivalate.

  Moreover, when manufacturing a modified ethylene-vinyl alcohol copolymer, the monomer which can be copolymerized with these monomers other than ethylene and vinyl ester may be used preferably in a small amount. This copolymerizable monomer includes, in addition to the monomer derived from the structural unit (8) described above, other alkenes such as acrylic acid, methacrylic acid, crotonic acid, maleic acid, and itaconic acid. Saturated carboxylic acid or its anhydride, salt, monoalkyl ester or dialkyl ester, etc .; Nitriles such as acrylonitrile and methacrylonitrile; Amides such as acrylamide and methacrylamide; Olefins such as vinyl sulfonic acid, allyl sulfonic acid and methallyl sulfonic acid Sulfonic acid or a salt thereof; alkyl vinyl ethers, vinyl ketone, N-vinyl pyrrolidone, vinyl chloride, vinylidene chloride and the like. Moreover, a vinyl silane compound can also be used as a monomer, and the amount of the vinyl silane compound introduced into the copolymer is preferably 0.0002 mol% or more and 0.2 mol% or less. Examples of the vinylsilane compound include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltri (β-methoxy-ethoxy) silane, γ-methacryloyloxypropylmethoxysilane, and the like. Among these vinylsilane compounds, vinyltrimethoxysilane and vinyltriethoxysilane are preferable.

  The solvent that can be used for the polymerization is not particularly limited as long as it is an organic solvent that can dissolve ethylene, vinyl ester, and ethylene-vinyl ester copolymer. Specific examples include alcohols such as methanol, ethanol, propanol, n-butanol and tert-butanol; dimethyl sulfoxide and the like. Among these, methanol is particularly preferable because removal and separation after the reaction is easy.

  Examples of the initiator that can be used for the polymerization include 2,2′-azobisisobutyronitrile, 2,2′-azobis- (2,4-dimethylvaleronitrile), and 2,2′-azobis- (4-methoxy). -2,4-dimethylvaleronitrile), 2,2'-azobis- (2-cyclopropylpropionitrile) and other azonitrile initiators; isobutyryl peroxide, cumylperoxyneodecanoate, diisopropylperoxycarbonate And organic peroxide initiators such as di-n-propyl peroxydicarbonate, t-butylperoxyneodecanoate, lauroyl peroxide, benzoyl peroxide, and t-butyl hydroperoxide.

  The polymerization temperature is usually about 20 to 90 ° C, preferably 40 to 70 ° C. The polymerization time is usually about 2 to 15 hours, preferably 3 to 11 hours. The polymerization rate is usually about 10 to 90%, preferably 30 to 80% with respect to the vinyl ester charged. The resin content in the solution after polymerization is about 5 to 85% by mass, preferably 20 to 70% by mass.

  After polymerization for a predetermined time or after reaching a predetermined polymerization rate, a polymerization inhibitor is added to the resulting copolymer solution as necessary, and unreacted ethylene gas is removed by evaporation. Remove. As a method for removing unreacted vinyl ester, for example, a copolymer solution is continuously supplied from the upper part of the tower filled with Raschig rings at a constant rate, and an organic solvent vapor such as methanol is blown from the lower part of the tower, A method of distilling a mixed vapor of an organic solvent such as methanol and unreacted vinyl ester from the top and taking out a copolymer solution from which unreacted vinyl ester has been removed from the bottom of the column is employed.

  Next, an alkali catalyst is added to the copolymer solution to saponify the copolymer present in the solution. The saponification method can be either a continuous type or a batch type. Examples of the alkali catalyst include sodium hydroxide, potassium hydroxide, alkali metal alcoholate, and the like. The saponification conditions are, for example, in the case of a batch system, the concentration of the alkali catalyst in the copolymer solution is about 10 to 50% by mass, the reaction temperature is about 30 to 65 ° C., and the amount of catalyst used is vinyl ester structural unit 1 It is preferable that about 0.02 to 1.0 mole per mole and saponification time is about 1 to 6 hours.

  The (modified) EVOH after the saponification reaction contains an alkali catalyst, by-product salts such as sodium acetate and potassium acetate, and other impurities. Therefore, it is preferable to remove these by neutralization and washing as necessary. . Here, when the (modified) EVOH after the saponification reaction is washed with water containing almost no metal ions such as ion-exchanged water, chloride ions, etc., part of sodium acetate, potassium acetate, etc. may remain. .

  The resin composition used for the barrier layer may contain one or more compounds selected from phosphoric acid compounds, carboxylic acids, and boron compounds.

  Specifically, the thermal stability during melt molding of the laminate can be improved by including a phosphoric acid compound in the resin composition. It does not specifically limit as a phosphoric acid compound, For example, various acids, such as phosphoric acid and phosphorous acid, its salt, etc. are mentioned. The phosphate may be contained in any form of, for example, a first phosphate, a second phosphate, and a third phosphate, and the counter cation species is not particularly limited. Alkaline earth metal ions are preferred. In particular, sodium dihydrogen phosphate, potassium dihydrogen phosphate, sodium hydrogen phosphate, or potassium hydrogen phosphate is preferred because of its high thermal stability improving effect.

  As a minimum of content of a phosphoric acid compound (phosphoric acid radical conversion content of a phosphoric acid compound in a dry resin composition), 1 mass ppm is preferred, 10 mass ppm is more preferred, and 30 mass ppm is still more preferred. On the other hand, as an upper limit of content of a phosphoric acid compound, 10,000 mass ppm is preferable, 1,000 mass ppm is more preferable, and 300 mass ppm is still more preferable. If the content of the phosphoric acid compound is less than 1 ppm by mass, coloring during melt molding may become severe. In particular, since the tendency is remarkable when the heat histories are accumulated, a molded product obtained by molding the resin composition pellet may be poor in recoverability. On the other hand, when the content of the phosphoric acid compound exceeds 10,000 ppm by mass, there is a risk that gels and blisters are likely to occur during molding.

  Moreover, by containing carboxylic acid in a resin composition, the effect of controlling the pH of a resin composition, preventing gelation, and improving thermal stability is acquired. As the carboxylic acid, those having a pKa at 25 ° C. of 3.5 or more are preferable. When a carboxylic acid such as oxalic acid, succinic acid, benzoic acid, or citric acid having a pKa at 25 ° C. of less than 3.5 is contained, it becomes difficult to control the pH of the resin composition, and coloring resistance and interlayer adhesion are reduced. There is a possibility that it cannot be obtained sufficiently. As such carboxylic acid, acetic acid or lactic acid is particularly preferable from the viewpoint of cost and the like.

  As a minimum of content of carboxylic acid (content of carboxylic acid in a dry resin composition), 1 mass ppm is preferred, 10 mass ppm is more preferred, and 50 mass ppm is still more preferred. On the other hand, the upper limit of the carboxylic acid content is preferably 10,000 mass ppm, more preferably 1,000 mass ppm, and even more preferably 500 mass ppm. If the carboxylic acid content is less than 1 ppm by mass, coloring may occur during melt molding. On the other hand, if the content of carboxylic acid exceeds 10,000 ppm by mass, interlayer adhesion may be insufficient.

Furthermore, the heat stability improvement effect is acquired by containing a boron compound in a resin composition. Specifically, for example, when a boron compound is added to a resin such as (modified) EVOH, a chelate compound is considered to be generated between (modified) EVOH and the boron compound, and by using such (modified) EVOH, It is possible to improve thermal stability and improve mechanical properties over normal (modified) EVOH. The boron compound is not particularly limited, and examples thereof include boric acids, boric acid esters, borates, and hydrogenated boric acids. Specifically, examples of boric acids include orthoboric acid (H ₃ BO ₃ ), metaboric acid, tetraboric acid, and the like, and examples of boric acid esters include triethyl borate, trimethyl borate, and the like. Examples of the borate include alkali metal salts, alkaline earth metal salts, and borax of the various boric acids. Of these, orthoboric acid is preferred.

  The lower limit of the boron compound content (the boron-converted content of the boron compound in the dry resin composition) is preferably 1 ppm by mass, more preferably 10 ppm by mass, and even more preferably 50 ppm by mass. On the other hand, the upper limit of the boron compound content is preferably 2,000 mass ppm, more preferably 1,000 mass ppm, and even more preferably 500 mass ppm. If the content of the boron compound is less than 1 ppm by mass, the effect of improving the thermal stability by adding the boron compound may not be obtained. On the other hand, when the content of the boron compound exceeds 2,000 ppm by mass, gelation tends to occur and there is a risk of forming defects.

  The method for containing the phosphoric acid compound, carboxylic acid or boron compound in the resin composition is not particularly limited. For example, a method of adding and kneading the resin composition to the resin composition when preparing a pellet or the like of the resin composition. Is preferably employed. The method of adding to the resin composition is not particularly limited, but the method of adding as a dry powder, the method of adding in a paste impregnated with a solvent, the method of adding in a suspended state in a liquid, or dissolving in a solvent. The method of adding as a solution can be illustrated. Among these, from the viewpoint of homogeneous dispersion, a method of dissolving in a solvent and adding as a solution is preferable. The solvent used in these methods is not particularly limited, but water is preferably used from the viewpoints of solubility of the additive, cost merit, ease of handling, completeness of work environment, and the like. At the time of these additions, a metal salt, other additives, etc., which will be described later, can be added simultaneously.

  In addition, as another method of containing a phosphoric acid compound, a carboxylic acid or a boron compound, a method of immersing pellets or strands of a resin composition obtained by an extruder or the like in a solution in which those substances are dissolved in a solvent Is preferable in that the substance can be uniformly dispersed. Also in this method, water is preferably used as the solvent for the same reason. By dissolving a metal salt described later in this solution, the metal salt can be contained simultaneously with the phosphoric acid compound and the like.

  The resin composition may contain a compound having a conjugated double bond having a molecular weight of 1,000 or less. By containing such a compound, the hue of the resin composition is improved, and a laminate having a good appearance can be produced. Examples of such compounds include conjugated diene compounds having a structure in which two carbon-carbon double bonds and three carbon-carbon single bonds are alternately connected, three carbon-carbon double bonds and four Conjugated triene compounds having a structure in which carbon-carbon single bonds are alternately connected (preferably 2,4,6-octatriene), 4 or more carbon-carbon double bonds and 5 or more carbon-carbon single bonds Examples thereof include conjugated polyene compounds having a structure in which bonds are alternately connected. In addition, a compound having a conjugated double bond may have a plurality of conjugated double bonds independently in one molecule, for example, a compound having three conjugated trienes in the same molecule such as tung oil. It is.

  Examples of the compound having a conjugated double bond include a carboxy group and a salt thereof, a hydroxyl group, an ester group, a carbonyl group, an ether group, an amino group, an imino group, an amide group, a cyano group, a diazo group, a nitro group, a sulfone group, Has various functional groups other than conjugated double bonds such as sulfoxide groups, sulfide groups, thiol groups, sulfonic acid groups and salts thereof, phosphoric acid groups and salts thereof, phenyl groups, halogen atoms, non-conjugated double bonds, and triple bonds. You may do it. Such a functional group may be directly bonded to the carbon atom in the conjugated double bond, or may be bonded to a position away from the conjugated double bond. In addition, the multiple bond in the functional group may be in a position capable of conjugating with a conjugated double bond. For example, 1-phenylbutadiene having a phenyl group, sorbic acid having a carboxy group, etc. Included in compounds with heavy bonds.

  Specific examples of the compound having a conjugated double bond include, for example, 2,4-diphenyl-4-methyl-1-pentene, 1,3-diphenyl-1-butene, and 2,3-dimethyl-1,3-butadiene. 4-methyl-1,3-pentadiene, 1-phenyl-1,3-butadiene, sorbic acid, myrcene and the like.

  The conjugated double bond in the compound having a conjugated double bond is not only an aliphatic conjugated double bond such as 2,3-dimethyl-1,3-butadiene and sorbic acid, but also 2,4-diphenyl. Aliphatic and aromatic conjugated double bonds such as -4-methyl-1-pentene and 1,3-diphenyl-1-butene are also included. However, from the viewpoint of obtaining a laminate having a more excellent appearance, a compound containing a conjugated double bond between aliphatic groups is preferable, and a compound containing a conjugated double bond having a polar group such as a carboxy group and a salt thereof or a hydroxyl group. Is also preferable. Further, a compound having a polar group and containing an aliphatic conjugated double bond is particularly preferable.

  The molecular weight of the compound having a conjugated double bond is preferably 1,000 or less. If the molecular weight exceeds 1,000, the surface smoothness and extrusion stability of the laminate may be deteriorated.

  The lower limit of the content of the compound having a conjugated double bond having a molecular weight of 1,000 or less in the resin composition is preferably 0.1 ppm by mass from the viewpoint of improving the effect exerted by the addition of the compound. 1 mass ppm is more preferable, 3 mass ppm is still more preferable, and 5 mass ppm is especially preferable. On the other hand, the upper limit of the content of the compound is preferably 3,000 ppm by mass, more preferably 2,000 ppm by mass, and 1,500 ppm by mass from the viewpoint of improving the effect exhibited by the addition of the compound. More preferred is 1,000 ppm by mass.

  The method for adding the compound having a conjugated double bond to the resin composition is not particularly limited, but when the resin is (modified) EVOH, the compound after polymerization and before saponification is added. The method of adding is preferable in terms of improving surface smoothness and extrusion stability. The reason for this is not necessarily clear, but it is considered that the compound having a conjugated double bond has an action to prevent alteration of (modified) EVOH before saponification and / or during the saponification reaction.

  Moreover, it is preferable to mix | blend the soft material whose Young's modulus in 23 degreeC is lower than the resin used for this barrier layer with the resin composition used for the said barrier layer as above-mentioned. Here, the soft material that can be used for the barrier layer preferably has a Young's modulus at 23 ° C. lower than that of the resin used for the barrier layer, more preferably 1000 MPa or less, and a range of 0.01 to 500 MPa. More preferably. If the Young's modulus at 23 ° C. of the soft material is higher than that of the resin, the effect exhibited by the dispersion of the soft material cannot be obtained, and crack resistance may be lowered. The resin used for the barrier layer usually has a Young's modulus at 23 ° C. of 700 MPa or more, but is preferably in the range of 750 to 3000 MPa.

  Moreover, the suitable embodiment of the soft material used for the said barrier layer and the suitable content in the resin composition for barrier layers are the same as that of the case of the soft material used for the said elastomer layer. That is, the soft material used for the barrier layer is preferably a compound having a functional group capable of reacting with a hydroxyl group, and specific examples of the functional group capable of reacting with a hydroxyl group are the same as those of the soft material used for the elastomer layer. is there. The soft material used for the barrier layer is preferably a compound having a molecular weight of 10,000 or less, more preferably a compound having a molecular weight of 5,000 or less, and still more preferably a compound having a molecular weight of 2,000 or less. And particularly preferably a compound having a molecular weight of 1,000 or less. Further, the soft material used for the barrier layer is preferably compatible with the resin. Furthermore, it is preferable that the content rate of the soft material in the said resin composition is 10-30 mass%.

  Specifically, as the soft material used for the barrier layer, butadiene rubber (BR), isoprene rubber (IR), styrene-butadiene copolymer rubber (SBR), natural rubber (NR), butyl rubber (IIR), isobutylene- p-methylstyrene, chlorosulfonated polyethylene rubber (CSM), ethylene propylene rubber (EPM, EPDM), ethylene-butene rubber, ethylene-octene rubber, chloroprene rubber (CR), acrylic rubber (ACM), nitrile rubber (NBR), silicone In addition to rubber such as rubber, these hydrogenated rubbers (for example, hydrogenated SBR), modified rubbers (for example, modified natural rubber, brominated-butyl rubber (Br-IIR), chlorinated butyl rubber (Cl-IIR), brominated Isobutylene-p-methylstyrene, etc.), liquid rubber (ie low molecular weight rubber) ), Or the like can be used. From the same viewpoint, the soft material used for the barrier layer includes polyethylene (PE), polypropylene (PP), ethylene-butene copolymer, styrene-ethylene-butene-styrene block copolymer (SEBS), styrene. In addition to polymers such as ethylene-propylene-styrene block copolymer (SEPS), styrene-isobutylene-chloromethylstyrene block copolymer, and polyamide, these hydrogenated products, modified products, and the like can be used. More specifically, maleic anhydride-modified hydrogenated styrene-ethylene-butadiene-styrene block copolymer, maleic anhydride-modified ultra-low density polyethylene and the like can be mentioned. In addition, these soft materials may be used individually by 1 type, and may blend and use 2 or more types.

  Furthermore, a known plasticizer may be used as the soft material used for the barrier layer. Here, as the plasticizer, phthalic acid plasticizers such as dibutyl phthalate, diheptyl phthalate, dioctyl phthalate (DOP), ditridecyl phthalate, and trioctyl melylate; phosphates such as tricresyl phosphate and trioctyl phosphate Plasticizers; fatty acid plasticizers such as tributyl citrate, dioctyl adipate, dioctyl sebacate, methylacetyl ricinoleate; epoxy plasticizers such as epoxidized soybean oil and diisodecyl-4,5-epoxyterola hydrophthalate; N-butyl In addition to amide plasticizers such as benzenesulfonamide, chlorinated paraffin, sunflower oil and the like can be mentioned. In addition, these soft materials may be used individually by 1 type, and may blend and use 2 or more types.

  For the same reason as in the case of the elastomer composition, a radical crosslinking agent may be added to the resin composition. Similarly, the content of the radical crosslinking agent in the resin composition is preferably 0.01 to 10% by mass, more preferably 0.05 to 9% by mass, and still more preferably 0.1 to 8% by mass. Specific examples of the radical crosslinking agent are as described above.

  In addition to the resin, phosphoric acid compound, carboxylic acid, boron compound, compound having a conjugated double bond, soft material, radical crosslinking agent, the resin composition includes a metal salt, a thermal stabilizer, and an ultraviolet absorber described later. A wide variety of additives such as antioxidants, colorants, fillers and the like can be appropriately selected and blended within a range that does not impair the object of the present invention. The content of additives other than the resin in the resin composition is preferably 50% by mass or less, more preferably 30% by mass or less, and still more preferably 10% by mass or less.

The resin composition has a melt viscosity (η _1A ) of 1 × 10 ² Pa · s or more and 1 × 10 ⁴ Pa · s at a temperature of 210 ° C. and a shear rate of 10 / sec for the same reason as in the case of the elastomer composition. s or less, the melt viscosity (η _2A ) at a temperature of 210 ° C. and a shear rate of 1,000 / sec is 1 × 10 ¹ Pa · s or more and 1 × 10 ³ Pa · s or less, and the melt viscosity ratio ( (η _2A / η _1A ) preferably satisfies the following formula (1A).
−0.8 ≦ (1/2) log ₁₀ (η _2A / η _1A ) ≦ −0.1 (1A)

Similarly, the value of (1/2) log ₁₀ (η _2A / η _1A ) calculated from the melt viscosity ratio (η _2A / η _1A ) is more preferably −0.6 or more, and −0 More preferably, it is 2 or less.

In the relationship between the melt kneading time and torque at at least one point at a temperature 10 to 80 ° C. higher than the melting point of the resin, the resin composition has a viscosity behavior stability (M ₁₀₀ / M ₂₀ , where M ₂₀ is 20 The value of the torque after minutes, M ₁₀₀ represents the torque after 100 minutes from the start of kneading) is preferably in the range of 0.5 to 1.5. The viscosity behavior stability value closer to 1 indicates that the viscosity change is smaller and the thermal stability (long run property) is more excellent.

Further, regarding the relationship between the viscosity of the resin composition and the viscosity of the elastomer composition, the melt viscosity (η of the elastomer composition with respect to the melt viscosity (η _2A ) of the resin composition at a temperature of 210 ° C. and a shear rate of 1,000 / sec. _2B ) is preferably 0.3, more preferably 0.4, and even more preferably 0.5 as the lower limit of the ratio (η _2B / η _2A ). On the other hand, the upper limit of the ratio (η _2B / η _2A ) of the melt viscosity (η _2B ) of the elastomer composition to the melt viscosity (η _2A ) of the resin composition is preferably 2, more preferably 1.5. 3 is more preferable. By making the melt viscosity ratio (η _2B / η _2A ) within the above specified range, the appearance of the laminate is improved by the multilayer coextrusion method, and the adhesion between the barrier layer and the elastomer layer is good. Thus, the durability of the laminate can be improved.

  The laminate preferably includes a metal salt in at least one of adjacent layers (for example, an adjacent barrier layer and an elastomer layer). In this case, the interlayer adhesion of the laminate can be greatly improved, and the laminate has excellent durability. The reason why interlayer adhesion can be improved by the inclusion of a metal salt is not necessarily clear, but for example, the bond formation reaction that occurs between the resin constituting the barrier layer and the elastomer constituting the elastomer layer is accelerated by the presence of the metal salt. It is conceivable. Specific examples of such bond formation reactions include a hydroxyl group exchange reaction that occurs between the carbamate group of TPU and the hydroxyl group of EVOH, and an addition reaction of the hydroxyl group of EVOH to the remaining isocyanate group in TPU.

  Although it does not specifically limit as said metal salt, The transition metal salt which belongs to the 4th period of an alkali metal salt, alkaline earth metal salt, or a periodic table is preferable from a viewpoint of improving interlayer adhesiveness more. Among these, alkali metal salts or alkaline earth metal salts are more preferable, and alkali metal salts are particularly preferable.

  Although it does not specifically limit as said alkali metal salt, For example, aliphatic carboxylate, aromatic carboxylate, phosphate, a metal complex etc., such as lithium, sodium, and potassium, are mentioned. Specific examples of the alkali metal salt include sodium acetate, potassium acetate, sodium phosphate, lithium phosphate, sodium stearate, potassium stearate, sodium salt of ethylenediaminetetraacetic acid, and the like. Among these, sodium acetate, potassium acetate, and sodium phosphate are particularly preferable because they are easily available.

  Although it does not specifically limit as said alkaline-earth metal salt, For example, acetate, such as magnesium, calcium, barium, beryllium, or phosphate is mentioned. Among these, magnesium or calcium acetate or phosphate is particularly preferable because it is easily available. When such an alkaline earth metal salt is contained, there is an advantage that the amount of heat-degraded resin adhering to the die of the molding machine during melt molding can be reduced.

  Although it does not specifically limit as a metal salt of the transition metal which belongs to the 4th period of the said periodic table, For example, carboxylate, phosphate, such as titanium, vanadium, chromium, manganese, iron, cobalt, nickel, copper, zinc And acetylacetonate salts.

  As a minimum of content of the above-mentioned metal salt (content of metal element conversion in a layered product), 1 mass ppm is preferred, 5 mass ppm is more preferred, 10 mass ppm is still more preferred, and 20 mass ppm is especially preferred. On the other hand, the upper limit of the content of the metal salt is preferably 10,000 ppm by mass, more preferably 5,000 ppm by mass, still more preferably 1,000 ppm by mass, and particularly preferably 500 ppm by mass. If the content of the metal salt is less than 1 mass ppm, the effect of improving interlayer adhesion may be reduced. On the other hand, if the content of the metal salt exceeds 10,000 ppm by mass, the appearance of the laminate may be deteriorated.

  The method of containing the metal salt in the resin composition forming the barrier layer or the elastomer composition forming the elastomer layer is not particularly limited, and a phosphoric acid compound or the like is added to the resin composition as described above. The method similar to the method of containing can be employ | adopted.

  In the laminate, the peel resistance between adjacent layers (for example, between barrier layers, between elastomer layers and between the barrier layer and the elastomer layer) is preferably 25 N / 25 mm or more, more preferably 27 N, from the viewpoint of interlayer adhesion. / 25 mm or more, more preferably 30 N / 25 mm or more. Here, the peel resistance is a value measured by a T-type peel test in accordance with JIS K 6854 at 23 ° C. and 50% RH atmosphere at a pulling speed of 50 mm / min.

  The method for producing the laminate is not particularly limited as long as the barrier layer and the elastomer layer can be laminated and adhered satisfactorily. For example, known methods such as co-extrusion, lamination, coating, bonding, adhesion, etc. The method is mentioned. As specific examples of the method for producing a multilayer structure of the present invention, (1) a resin composition containing EVOH and an elastomer composition containing an elastomer are prepared, and a barrier layer and an epoxy composition are produced by a multilayer coextrusion method using these compositions. A method for producing a laminate having an elastomer layer, and (2) a resin composition containing EVOH and an elastomer composition containing an elastomer are prepared, and a plurality of laminates are produced using these, and then a plurality of laminates are prepared. For example, a method of producing a laminate having a barrier layer and an elastomer layer by superimposing them with an adhesive and stretching them may be mentioned. Among these, the method (1) is preferable from the viewpoint of high productivity and excellent interlayer adhesion.

  In the multilayer coextrusion method, the resin composition forming the barrier layer and the elastomer composition forming the elastomer layer are heated and melted and supplied to the extrusion die from different extruders and pumps through respective flow paths. Then, after being extruded from the extrusion die in multiple layers, the laminate is formed by laminating and bonding. As this extrusion die, for example, a multi-manifold die, a field block, a static mixer or the like can be used.

  Moreover, the said laminated body may laminate | stack the support layer for supporting this laminated body on the both surfaces or single side | surface of the laminated body which consists of a barrier layer and an elastomer layer. The support layer is not particularly limited, and for example, a synthetic resin layer or the like usually used as the support layer can be used. In addition, it does not specifically limit as a lamination method to the barrier layer or elastomer layer of a support layer, For example, the adhesion method by an adhesive agent, the extrusion lamination method, etc. are mentioned.

<Coating rubber>
The pneumatic tire of the present invention includes a belt 5 composed of one or more belt layers on the outer side in the tire radial direction of the carcass 4, and the belt layer is formed by coating a cord, preferably a steel cord, with a coating rubber. The rubber composition obtained by blending 0.1 to 10 parts by mass of the compound represented by the general formula (1) with respect to 100 parts by mass of the rubber component in at least one coating rubber of the belt layer, or The compound represented by the above general formula (2) is 60 to 100% by weight, the compound represented by the above general formula (3) and n = 2 is 0 to 20% by weight based on 100 parts by mass of the rubber component, and the above general A composition comprising 0 to 10% by weight of the compound represented by the formula (3) and n = 3 and 0 to 10% by weight of the compound represented by the general formula (3) and n = 4 to 6 in total. 0.1 to 10 parts by weight Compositions are applied.

  The rubber component of the rubber composition for coating rubber is not particularly limited as long as it exhibits rubber elasticity, but other than natural rubber (NR); vinyl aromatic hydrocarbon / conjugated diene copolymer, polyisoprene rubber All known rubbers such as (IR), butadiene rubber (BR), butyl rubber (IIR), halogenated butyl rubber, and synthetic rubbers such as ethylene-propylene rubber can be used. Among these, natural rubber (NR) is preferable. The rubber component may be used alone or in combination of two or more. From the viewpoint of the adhesive property with the cord and the fracture property of the rubber composition, the rubber component is composed of at least one of natural rubber and polyisoprene rubber, or contains 50% by mass or more of natural rubber and the balance is synthetic rubber. Is preferred.

  In the compound represented by the general formula (1) blended in the rubber composition for a coating rubber, R in the formula is a divalent aliphatic group having 1 to 16 carbon atoms or a divalent aromatic group. Represents. As a compound represented by General formula (1), the compound represented by General formula (2) is mentioned, for example. R in the general formula (2) has the same meaning as R in the general formula (1).

  Here, examples of the divalent aliphatic group having 1 to 16 carbon atoms include linear or branched alkylene such as methylene group, ethylene group, butylene group, isobutylene group, octylene group, and 2-ethylhexylene group. Group, vinylene group (ethenylene group), butenylene group, octenylene group or other linear or branched alkenylene group, alkylene group or alkylene group or alkenylene in which the hydrogen atom of alkenylene group is substituted with hydroxyl group or amino group And alicyclic groups such as a cyclohexylene group. Examples of the divalent aromatic group include an optionally substituted phenylene group and an optionally substituted naphthylene group. Among these, in view of availability, an alkylene group having 2 to 10 carbon atoms and a phenylene group are preferable, and an ethylene group, butylene group, octylene group, and phenylene group are particularly preferable.

  Specific examples of the compound of the general formula (1) include malonic acid bis (2-hydroxyphenyl) ester, succinic acid bis (2-hydroxyphenyl) ester, fumaric acid bis (2-hydroxyphenyl) ester, maleic acid bis (2-hydroxyphenyl) ester, malic acid bis (2-hydroxyphenyl) ester, itaconic acid bis (2-hydroxyphenyl) ester, citraconic acid bis (2-hydroxyphenyl) ester, adipic acid bis (2-hydroxyphenyl) Ester, bis (2-hydroxyphenyl) tartrate, bis (2-hydroxyphenyl) azelaic acid, bis (2-hydroxyphenyl) sebacate, bis (2-hydroxyphenyl) cyclohexanedicarboxylate, bis terephthalate 2-hydroxyphenyl) ester, isophthalic acid bis (2-hydroxyphenyl) ester, malonic acid bis (3-hydroxyphenyl) ester, succinic acid bis (3-hydroxyphenyl) ester, fumaric acid bis (3-hydroxyphenyl) ester , Maleic acid bis (3-hydroxyphenyl) ester, malic acid bis (3-hydroxyphenyl) ester, itaconic acid bis (3-hydroxyphenyl) ester, citraconic acid bis (3-hydroxyphenyl) ester, adipic acid bis (3 -Hydroxyphenyl) ester, tartrate bis (3-hydroxyphenyl) ester, azelaic acid bis (3-hydroxyphenyl) ester, sebacic acid bis (3-hydroxyphenyl) ester, cyclohexanedicarboxylic acid bis (3- Droxyphenyl) ester, terephthalic acid bis (3-hydroxyphenyl) ester, isophthalic acid bis (3-hydroxyphenyl) ester, malonic acid bis (4-hydroxyphenyl) ester, succinic acid bis (4-hydroxyphenyl) ester, Fumaric acid bis (4-hydroxyphenyl) ester, maleic acid bis (4-hydroxyphenyl) ester, itaconic acid bis (4-hydroxyphenyl) ester, citraconic acid bis (4-hydroxyphenyl) ester, adipic acid bis (4- Hydroxyphenyl) ester, tartaric acid bis (4-hydroxyphenyl) ester, azelaic acid bis (4-hydroxyphenyl) ester, sebacic acid bis (4-hydroxyphenyl) ester, cyclohexanedicarboxylic acid bis (4-hydride) Roxyphenyl) ester, terephthalic acid bis (4-hydroxyphenyl) ester, isophthalic acid bis (4-hydroxyphenyl) ester, and the like.

  Among these, malonic acid bis (3-hydroxyphenyl) ester, succinic acid bis (3-hydroxyphenyl) ester, fumaric acid bis (3-hydroxyphenyl) ester, maleic acid bis (3-hydroxyphenyl) ester, malic acid Bis (3-hydroxyphenyl) ester, itaconic acid bis (3-hydroxyphenyl) ester, citraconic acid bis (3-hydroxyphenyl) ester, adipic acid bis (3-hydroxyphenyl) ester, tartrate bis (3-hydroxyphenyl) Esters, azelaic acid bis (3-hydroxyphenyl) ester, sebacic acid bis (3-hydroxyphenyl) ester, cyclohexanedicarboxylic acid bis (3-hydroxyphenyl) ester, terephthalic acid bis (3-hydroxyphenyl) Steal and bis (3-hydroxyphenyl) esters of isophthalic acid are preferred, and bis (3-hydroxyphenyl) succinic acid ester, bis (3-hydroxyphenyl) adipic acid ester, bis (3-hydroxyphenyl) sebacic acid ester, terephthalic acid Acid bis (4-hydroxyphenyl) ester and isophthalic acid bis (4-hydroxyphenyl) ester are preferred.

  The method for producing the compound represented by the general formula (1) is not particularly limited. For example, as disclosed in JP-A-2005-290373, a dicarboxylic acid halide, catechol, resorcin, and hydroquinone are present in the presence of a base. It can be produced by reacting in the absence or absence.

  Here, when a dicarboxylic acid halide and resorcin are used, the compound represented by the general formula (2) and the general formula (3) containing the compound represented by the general formula (2) as a main component. A composition (mixture) consisting of the compound to be obtained is obtained. In addition, R in General formula (3) is synonymous with R in General formula (1), and n shows the integer of 2-6.

  For example, in a composition comprising a compound represented by the general formula (2) and a compound represented by the general formula (3) obtained when resorcin is used in the above reaction, the general formula (2 ) Is 60 to 100% by weight, the compound of n = 2 in the general formula (3) is 0 to 20% by weight, the compound of n = 3 in the general formula (3) is 0 to 10% by weight, The compound of n = 4-6 in Formula (3) is contained about 10 weight% in total. These ratios can be controlled by changing the molar ratio of the compound represented by the general formula (4) and resorcin. When the compound represented by the general formula (2) is 60% by weight or more, wet heat adhesiveness when blended with rubber is improved. Judging from the viewpoint of improving wet heat adhesion, the content of the compound represented by the general formula (2) is more preferably 70 to 100% by weight, still more preferably 80 to 100% by weight.

  When the compound represented by the general formula (1) is blended with the rubber composition for coating rubber, the compounding amount of the compound represented by the general formula (1) is 0.1% with respect to 100 parts by mass of the rubber component. It is the range of 10-10 mass parts, and the range of 0.3-6 mass parts is preferable. When the compounding amount of the compound represented by the general formula (1) is 0.1 parts by mass or more with respect to 100 parts by mass of the rubber component, the wet heat adhesiveness of the rubber composition is improved and is 10 parts by mass or less. , Which is preferable in that the bloom of the compound represented by the general formula (1) can be suppressed.

  Moreover, when mix | blending the composition consisting of the compound represented by the said General formula (2) and the compound represented by the said General formula (3) in the said rubber composition for coating rubbers, the compounding quantity of this composition is The range is from 0.1 to 10 parts by weight, preferably from 0.3 to 6 parts by weight, based on 100 parts by weight of the rubber component. When the blending amount of the composition containing the compound represented by the general formula (2) as a main component is 0.1 parts by mass or more with respect to 100 parts by mass of the rubber component, the wet heat adhesiveness of the rubber composition is improved. When it is 10 parts by mass or less, it is preferable in that the bloom of the composition containing the compound represented by the general formula (2) as a main component can be suppressed.

  The rubber composition for coating rubber is preferably further blended with sulfur. Here, although there is no restriction | limiting in particular in the sulfur mix | blended with a rubber composition, It is preferable to use a powder normally. Moreover, the range of 1-10 mass parts is preferable with respect to 100 mass parts of rubber components, and the range of 2-9 mass parts is still more preferable, and the range of 3-7 mass parts is still more preferable. When the amount of sulfur is 1 part by mass or more with respect to 100 parts by mass of the rubber component, it is preferable in terms of adhesiveness to the cord, and when it is 10 parts by mass or less, generation of an excessive adhesive layer is suppressed. This is preferable because the adhesiveness does not decrease. Moreover, if the compounding quantity of sulfur exists in the range of 2-9 mass parts, adhesiveness with a cord will become especially favorable.

  The rubber composition for coating rubber can further contain an organic acid cobalt salt. Examples of the organic acid cobalt salt include cobalt naphthenate, cobalt stearate, cobalt neodecanoate, cobalt rosinate, cobalt versatate and cobalt tall oil. The organic acid cobalt salt may be a complex salt in which a part of the organic acid is replaced with boric acid or the like. Specific examples include manobond (trademark: manufactured by OMG). As a compounding quantity of organic acid cobalt salt, it is preferable to mix | blend 0.03-1 mass part as a cobalt quantity with respect to 100 mass parts of said rubber components. When the compounding amount of the organic acid cobalt salt is 0.03 parts by mass or more as a cobalt amount with respect to 100 parts by mass of the rubber component, the adhesion between the rubber composition and the cord is improved, and when it is 1 part by mass or less, Aging of the rubber composition is suppressed.

  The rubber composition for coating rubber includes the above compound or composition, rubber component, sulfur, organic acid cobalt salt, filler such as carbon black and silica, softener such as aroma oil, hexamethylenetetramine, pentamethoxy. Methylene donors such as methoxymethylated melamines such as methylmelamine and hexamethylenemethylmelamine, vulcanization accelerators, vulcanization accelerators, anti-aging agents, etc. It can mix | blend suitably. The method for preparing the rubber composition is not particularly limited. For example, the rubber compound is prepared by kneading the compound or composition, sulfur, organic acid cobalt salt, and various compounding agents into a rubber component using a Banbury mixer or a roll. be able to.

  The cord to be bonded to the rubber composition for coating rubber, preferably a steel cord, is plated with brass, zinc, or a metal containing nickel or cobalt to improve the adhesion to rubber. It is particularly preferable that brass plating is applied. Further, the size, the number of twists, the twisting conditions and the like of the cord are appropriately selected according to the required performance of the tire.

  A rubber composition prepared by kneading the above-mentioned rubber component, the above-mentioned compound or a composition containing it as a main component, sulfur, an organic acid cobalt salt and various compounding agents, into a sheet shape with a roll or the like, and further processing The belt layer can be formed by molding the two rubber sheets so as to sandwich the cord. The formed belt layer is laminated on the outer side in the tire radial direction of the carcass 4 according to a conventional method, and constitutes the pneumatic tire of the present invention together with other members.

  Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to the following examples.

<Synthesis of bis (3-hydroxyphenyl) ester of adipic acid>
According to the manufacture example 1 of Unexamined-Japanese-Patent No. 2005-290373, the adipic acid bis (3-hydroxyphenyl) ester was synthesize | combined.

<Synthesis of Composition A mainly composed of bis (3-hydroxyphenyl) adipate>
According to Production Example 2 of JP-A-2005-290373, 89% by weight of adipic acid bis (3-hydroxyphenyl) ester is represented by the above formula (3), where n is 2, and R is tetramethylene. 7% by weight of the compound of the group [— (CH ₂ ) ₄ —] represented by the above formula (3), wherein n is 3, and R is a tetramethylene group [— (CH ₂ ) ₄ —] A composition containing 2% by weight of the above compound and 2% by weight of the raw material resorcin was synthesized.

<Synthesis of Composition B mainly composed of bis (3-hydroxyphenyl) adipate>
According to Production Example 3 of JP-A-2005-290373, 73.4% by weight of adipic acid bis (3-hydroxyphenyl) ester is represented by the above formula (3), where n is 2, and R is A compound which is a tetramethylene group [— (CH ₂ ) ₄ —] is represented by 13.9 wt% of the above formula (3), in which n is 3, and R is a tetramethylene group [— (CH ₂ ) ₄ -], compound 3.0 wt%, represented by the above formula (3), at n in the formula 4, R is a tetramethylene group [- a] compounds wherein - (CH _{2) 4} 0.8% by weight of a compound represented by the above formula (3), wherein n is 5, and R is a tetramethylene group [— (CH ₂ ) ₄ —] A composition containing 2.9% by weight of resorcin was synthesized.

<Synthesis of succinic acid bis (3-hydroxyphenyl) ester>
According to Production Example 4 of JP-A-2005-290373, succinic acid bis (3-hydroxyphenyl) ester was synthesized.

<Synthesis of sebacic acid bis (3-hydroxyphenyl) ester>
Sebacic acid bis (3-hydroxyphenyl) ester was synthesized according to Production Example 5 of JP-A-2005-290373.

<Synthesis of terephthalic acid bis (3-hydroxyphenyl) ester>
Terephthalic acid bis (3-hydroxyphenyl) ester was synthesized according to Production Example 6 of JP-A-2005-290373.

<Synthesis of isophthalic acid bis (3-hydroxyphenyl) ester>
According to the manufacture example 7 of Unexamined-Japanese-Patent No. 2005-290373, the isophthalic acid bis (3-hydroxyphenyl) ester was synthesize | combined.

<Preparation of rubber composition>
An unvulcanized rubber composition was prepared by kneading and mixing with a rubber compounding formulation shown in Table 1 using a 2200 mL Banbury mixer.

* 1 N, N′-dicyclohexyl-2-benzothiazylsulfenamide, manufactured by Ouchi Shinsei Chemical Industry Co., Ltd., trade name: Noxeller DZ.
* 2 N-phenyl-N ′-((1,3-dimethylbutyl) -p-phenylenediamine, manufactured by Ouchi Shinsei Chemical Co., Ltd., trade name: NOCRACK 6C.
* 3 Made by OMG, trade name: Manobond C22.5, cobalt content = 22.5% by mass.

<The manufacturing method of the laminated body 1>
As nylon 6 pellet (A-1), Toray Industries, Inc. product name "CM1061" was used.

  Moreover, the number of hydroxyl groups per molecule obtained by reacting 1,4-butanediol and adipic acid is 2.0, and the polyester diol having a number average molecular weight of 1,000 is 68.8% by mass, A mixture of 27.5% by mass of 4,4-diphenylmethane diisocyanate and 3.7% by mass of 1,4-butanediol was melt-kneaded for 20 minutes in a multi-screw type extruder (die temperature 260 ° C.). A plastic polyurethane resin TPU (B-1) was produced and then pelletized to obtain TPU pellets (B-1).

Using the nylon 6 pellet (A-1) and the TPU pellet (B-1), a multilayer structure having 24 barrier layers and 25 elastomer layers is alternately formed by the resin composition constituting the pellets. As described above, a 49-layer feed block was supplied to a co-extruder as a molten state at 210 ° C., and co-extrusion was performed to join them to form a multilayer laminate. The melt of pellets (A-1) and pellets (B-1) to be merged is extruded by changing each layer flow path so that it gradually becomes thicker from the surface side toward the center side in the feed block. The multilayer structure was extruded so that the thickness of each layer was uniform. In addition, the slit shape was designed so that the adjacent barrier layer and elastomer layer had substantially the same layer thickness. The thus obtained laminate consisting of a total of 49 layers was rapidly cooled and solidified on a casting drum which was kept at a surface temperature of 25 ° C. and electrostatically applied. The cast film obtained by rapid cooling and solidification was pressure-bonded onto a release paper and wound up. In addition, the flow path shape and the total discharge amount are set so that the time from when the melt of the pellet (A-1) and the pellet (B-1) merges to when rapidly solidified on the casting drum is about 4 minutes. Set.
The cast film obtained as described above was subjected to cross-sectional observation with DIGITAL MICROSCOPE VHX-900 (manufactured by KEYENCE). As a result, the average thickness of each of the barrier layer and the elastomer layer was 0.5 μm, and the overall average thickness was Was 12.5 μm.
Next, the cast film was irradiated with an electron beam having an acceleration voltage of 200 kV and an irradiation dose of 200 kGy by using an electron beam accelerator [manufactured by Nissin High Voltage Co., Ltd., model name “Curetron EBC200-100”]. Got.

<The manufacturing method of the laminated body 2>
Instead of nylon 6 pellets (A-1), polyvinylidene chloride pellets (A-2) [manufactured by Asahi Dow Co., Ltd., trade name “Saran”] were used in the same manner as in the manufacturing method of laminate 1. Thus, a laminate 2 was obtained.

<Production method of butyl rubber inner liner>
With respect to 100 parts by weight of Br-IIR [manufactured by JSR Corporation, Bromobutyl 2244], 60 parts by weight of GPF carbon black [Asahi Carbon Co., Ltd., # 55], 7 parts by weight of SUNPAR 2280 [manufactured by Nippon Sun Oil Co., Ltd.] Parts, 1 part by weight of stearic acid [Asahi Denka Kogyo Co., Ltd.], 1.3 parts by weight of NOCCELER DM [Ouchi Shinsei Chemical Co., Ltd.], 3 parts by weight of zinc oxide [Shiramizu Chemical Co., Ltd.] A rubber composition was prepared by blending 0.5 part by weight of sulfur [manufactured by Karuizawa Smelter], and a butyl rubber inner liner having a thickness of 1 mm was produced using the rubber composition.

<Method for producing EVOH inner liner>
In a pressurized reaction vessel, 2 parts by weight of ethylene-vinyl alcohol copolymer (MFR: 5.5 g / 10 min (190 ° C., 2160 g load)) having an ethylene content of 44 mol% and a saponification degree of 99.9% and N -8 parts by weight of methyl-2-pyrrolidone was charged, and the mixture was heated and stirred at 120 ° C for 2 hours to completely dissolve the ethylene-vinyl alcohol copolymer. To this was added 0.4 part by weight of glycidol as an epoxy compound, and the mixture was heated at 160 ° C. for 4 hours. After the heating, it was precipitated in 100 parts by weight of distilled water, and N-methyl-2-pyrrolidone and unreacted glycidol were sufficiently washed with a large amount of distilled water to obtain a modified ethylene-vinyl alcohol copolymer. Further, the resulting modified ethylene-vinyl alcohol copolymer was fined to a particle size of about 2 mm with a pulverizer, and then sufficiently washed with a large amount of distilled water again. The washed particles were vacuum-dried at room temperature for 8 hours, and then melted at 200 ° C. using a twin-screw extruder and pelletized.

Using the modified ethylene-vinyl alcohol copolymer pellets, a 40 mmφ extruder (PLABOR GT-40-A manufactured by Plastics Engineering Laboratory) and a T-die film forming machine were used to form a film under the following extrusion conditions. A monolayer film having a thickness of 12 μm was obtained.
Type: Single screw extruder (non-vent type)
L / D: 24
Diameter: 40mmφ
Screw: single-flight full flight type, surface nitrided steel Screw rotation speed: 40rpm
Die: 550 mm wide coat hanger die Lip gap: 0.3 mm
Cylinder, die temperature setting: C1 / C2 / C3 / adapter / die = 180/200/210/210/210 (° C.)

  Next, using the electron beam irradiation apparatus “Curetron EBC200-100 for production” manufactured by Nissin High Voltage Co., Ltd., the film was irradiated with an electron beam under the conditions of an acceleration voltage of 200 kV and an irradiation energy of 30 Mrad, and then subjected to crosslinking treatment. To produce an EVOH inner liner.

<Production of tire>
A belt coated with a steel cord (1 × 5 structure, strand diameter 0.25 mm) plated with brass (Cu; 63 mass%, Zn; 37 mass%) is coated with the rubber composition prepared as described above. A layer was formed. A radial tire of size 195 / 65R15 having the structure shown in FIG. 1 was prototyped using the belt layer and the inner liner by a conventional method. “Skid base gauge” in Tables 2 and 3 means the thickness from the groove bottom of the tread to the tread undercushion. The durability of adhesion between the steel cord and the coating rubber in the belt layer of the obtained tire was evaluated by the following method. In addition, a drum test was performed on the obtained tire to evaluate the rolling resistance of the tire. Furthermore, the weight of the tire was evaluated as follows. Moreover, the crack of the inner liner after the drum test was visually observed. Furthermore, the gas barrier property of the used inner liner was evaluated by the following method. The results are shown in Tables 2 and 3.

(1) Durability of adhesion between steel cord and coating rubber in belt layer After leaving the test tire in a constant temperature and humidity chamber maintained at 100 ° C. and 95% RH for 5 weeks, the belt layer was taken out of the tire and the belt The steel cord in the layer was pulled at a rate of 50 mm / min with a tensile tester, the rubber coating state of the exposed steel cord was visually observed, the coverage was determined, and the index of the comparative example 1 was represented by 40. did. The larger the index value, the higher the adhesion durability and the better.

(2) Rolling resistance Rotate the drum while bringing the test tire into contact with the drum, raise it to a certain speed, turn off the drum drive switch, rotate the drum freely, and determine the rolling resistance from the degree of deceleration. The rolling resistance of tire No. 1 is shown as an index with 100 as the rolling resistance. It shows that rolling resistance is so small that an index value is small.

(3) Tire Weight The weight of each test tire was displayed as an index, with the weight of the tire of Comparative Example 1 being 100. The smaller the index value, the lighter and better the tire.

(4) Cracking of inner liner The test tire was pushed at a pressure of 6 km on a rotating drum corresponding to a speed of 80 km / h at an air pressure of 140 kPa and traveled 10,000 km. The appearance of the inner liner of the tire after running the drum was visually observed to evaluate the presence or absence of cracks.

(5) Gas barrier property of inner liner The inner liner was conditioned at 20 ° C. and 65% RH for 5 days. In accordance with JIS K7126 (isobaric method) using the MOCON OX-TRAN 2/20 type manufactured by Modern Control Co., Ltd. under the conditions of 20 ° C. and 65% RH using the two inner liners that have been humidity-controlled. The air permeability was measured, the average value was obtained, and the average value of the air permeability of the inner liner used in Comparative Example 1 was taken as 100 and indicated as an index. The lower the index value, the better the gas barrier property.

  From Tables 2 and 3, a rubber composition containing a barrier layer and an elastomer layer applied to the inner liner and further blended with the specific compound or a composition containing the compound as a main component is used as the belt layer. It can be seen that by applying to the coating rubber, the rolling resistance of the tire can be reduced while greatly improving the durability of adhesion between the steel cord and the rubber in the belt layer.

1 Bead part 2 Side wall part 3 Tread part 4 Carcass 5 Belt 6 Inner liner 7 Bead core

Claims (15)

A carcass, a belt composed of one or more belt layers disposed on the outer side in the tire radial direction of the carcass, and an inner liner disposed on the tire inner surface side of the carcass,
A laminate comprising a total of 7 or more layers of a barrier layer made of a resin composition having a thickness of 0.001 to 10 μm and an elastomer layer having a thickness of 0.001 to 40 μm made of an elastomer composition, Apply,
The belt layer is formed by coating a cord with a coating rubber, and at least one coating rubber of the belt layer has the following general formula (1) with respect to 100 parts by mass of a rubber component:

(Wherein R represents a divalent aliphatic group having 1 to 16 carbon atoms, or a divalent aromatic group) A pneumatic tire characterized by being applied. A carcass, a belt composed of one or more belt layers disposed on the outer side in the tire radial direction of the carcass, and an inner liner disposed on the tire inner surface side of the carcass,
A laminate comprising a total of 7 or more layers of a barrier layer made of a resin composition having a thickness of 0.001 to 10 μm and an elastomer layer having a thickness of 0.001 to 40 μm made of an elastomer composition, Apply,
The belt layer is formed by covering a cord with a coating rubber, and at least one coating rubber of the belt layer is represented by the following general formula (2) with respect to 100 parts by mass of a rubber component:

(Wherein R represents a divalent aliphatic group having 1 to 16 carbon atoms or a divalent aromatic group), 60 to 100% by weight of a compound represented by the following general formula (3):

(Wherein R represents a divalent aliphatic group having 1 to 16 carbon atoms or a divalent aromatic group, and n represents an integer of 2 to 6) and n = 2 is a compound represented by 0 0 to 10% by weight, 0 to 10% by weight of the compound represented by the above general formula (3) and n = 3 and 0 to 10% by weight of the compound represented by the above general formula (3) and n = 4 to 6 A pneumatic tire characterized by applying a rubber composition comprising 0.1 to 10 parts by mass of a composition comprising% by weight.   The pneumatic tire according to claim 1 or 2, wherein the elastomer composition constituting the elastomer layer is obtained by dispersing a soft material having a Young's modulus at 23 ° C lower than that of the elastomer in the elastomer.   The pneumatic tire according to claim 3, wherein the soft material has a molecular weight of 10,000 or less.   The pneumatic tire according to claim 4, wherein the soft material has a molecular weight of 1,000 or less.   The pneumatic tire according to claim 1 or 2, wherein the elastomer composition constituting the elastomer layer includes a polyurethane-based thermoplastic elastomer.   The pneumatic tire according to claim 1 or 2, wherein the resin composition constituting the barrier layer is obtained by dispersing a soft material having a Young's modulus at 23 ° C lower than that of the resin in the resin.   The pneumatic tire according to claim 7, wherein the soft material has a functional group capable of reacting with a hydroxyl group.   The pneumatic tire according to claim 7, wherein the soft material has a molecular weight of 10,000 or less.   The pneumatic tire according to claim 9, wherein the soft material has a molecular weight of 1,000 or less.   The resin composition constituting the barrier layer is at least selected from the group consisting of an ethylene-vinyl alcohol copolymer, a modified ethylene-vinyl alcohol copolymer, a polyamide resin, a polyvinylidene chloride resin, polyethylene terephthalate, and polyacrylonitrile. The pneumatic tire according to claim 1, comprising one kind.   The pneumatic tire according to claim 11, wherein the resin composition constituting the barrier layer contains an ethylene-vinyl alcohol copolymer and / or a modified ethylene-vinyl alcohol copolymer.   The pneumatic tire according to claim 1 or 2, wherein the barrier layer and / or the elastomer layer is crosslinked by irradiation with active energy rays.   The pneumatic tire according to claim 1 or 2, wherein a rubber component of a rubber composition applied to the coating rubber includes natural rubber.   The pneumatic tire according to claim 1 or 2, wherein the rubber composition applied to the coating rubber further contains 2 to 9 parts by mass of sulfur with respect to 100 parts by mass of the rubber component.

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